Document and Entity Information	6 Months Ended
Document and Entity Information	Jun. 30, 2010	Jul. 23, 2010
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2010
Document Fiscal Year Focus	2010
Document Fiscal Period Focus	Q2
Entity Registrant Name	AMERICAN TOWER CORP /MA/
Entity Central Index Key	0001053507
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		401,142,346

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)
In Thousands, unless otherwise specified

6 Months Ended

12 Months Ended

Jun. 30, 2010

Dec. 31, 2009

CURRENT ASSETS:

Cash and cash equivalents

$ 302,893

$ 247,293

Restricted cash

52,566

47,836

Short-term investments and available-for-sale securities

27,891

^[1]

9,776

^[1]

Accounts receivable, net

48,872

67,949

Prepaid and other current assets

113,844

92,791

Deferred income taxes

224,472

189,451

Total current assets

770,538

655,096

PROPERTY AND EQUIPMENT, net

3,188,461

3,158,356

GOODWILL

2,255,943

2,255,234

OTHER INTANGIBLE ASSETS, net

1,596,492

1,598,525

^[2]

DEFERRED INCOME TAXES

96,369

198,185

NOTES RECEIVABLE AND OTHER LONG-TERM ASSETS

678,120

651,894

TOTAL

8,585,923

8,517,290

CURRENT LIABILITIES:

Accounts payable and accrued expenses

205,040

185,138

Accrued interest

23,662

23,538

Current portion of long-term obligations

1,610

70,521

Unearned revenue

128,508

112,047

Total current liabilities

358,820

391,244

LONG-TERM OBLIGATIONS

4,152,041

4,141,060

OTHER LONG-TERM LIABILITIES

645,052

666,861

Total liabilities

5,155,913

5,199,165

COMMITMENTS AND CONTINGENCIES

STOCKHOLDERS' EQUITY:

Preferred Stock: $.01 par value; 20,000,000 shares authorized; no shares issued or outstanding

Class A Common Stock: $.01 par value, 1,000,000,000 shares authorized, 484,490,239 and 479,703,633 shares issued, and 401,745,103 and 401,596,984 shares outstanding, respectively

4,845

4,797

Additional paid-in capital

8,503,052

8,393,643

Accumulated deficit

(1,913,549)

(2,109,532)

Accumulated other comprehensive income (loss)

(9,829)

(12,649)

Treasury stock (82,745,136 and 78,106,649 shares at cost, respectively)

(3,157,520)

(2,961,177)

Total American Tower Corporation stockholders' equity

3,426,999

3,315,082

Noncontrolling interest

3,011

3,043

Total stockholders' equity

3,430,010

3,318,125

TOTAL

$ 8,585,923

$ 8,517,290

[1]	Consists of available-for-sale securities traded on active markets as well as certain Brazilian Treasury securities that are highly liquid and actively traded in over-the-counter markets.
[2]	December 31, 2009 balances have been revised to reflect purchase accounting adjustments.

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Jun. 30, 2010	Dec. 31, 2009
Preferred Stock, par value	$ 0.01	$ 0.01
Preferred Stock, shares authorized	20,000,000	20,000,000
Preferred Stock, shares issued	0	0
Preferred Stock, shares outstanding	0	0
Class A Common Stock, par value	$ 0.01	$ 0.01
Class A Common Stock, shares authorized	1,000,000,000	1,000,000,000
Class A Common Stock, shares issued	484,490,239	479,703,633
Class A Common Stock, shares outstanding	401,745,103	401,596,984
Treasury stock, shares	82,745,136	78,106,649

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2010	Jun. 30, 2009
REVENUES:
Rental and management	$ 456,481	$ 406,751	$ 900,299	$ 802,698
Network development services	13,456	16,607	24,072	29,338
Total operating revenues	469,937	423,358	924,371	832,036
OPERATING EXPENSES:
Rental and management	105,773	92,330	206,197	182,420
Network development services	6,426	10,243	12,471	17,858
Depreciation, amortization and accretion	110,403	102,463	221,238	202,331
Selling, general, administrative and development expense (including stock-based compensation expense of $13,228, $12,836, $26,792, and $37,174, respectively)	53,582	49,861	107,109	107,493
Other operating expenses	5,037	2,014	9,791	5,203
Total operating expenses	281,221	256,911	556,806	515,305
OPERATING INCOME	188,716	166,447	367,565	316,731
Costs of operations
Interest income, TV Azteca, net of interest expense of $372, $372, $744 and $744, respectively	3,585	3,585	7,084	7,084
Interest income	694	482	1,196	981
Interest expense	(56,074)	(62,654)	(114,491)	(124,222)
Loss on retirement of long-term obligations	(35)	(5,994)	(35)	(5,994)
Other (expense) income	(6,719)	983	(6,323)	1,054
Total other expense	(58,549)	(63,598)	(112,569)	(121,097)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INCOME ON EQUITY METHOD INVESTMENTS	130,167	102,849	254,996	195,634
Income tax provision	(30,352)	(51,428)	(58,741)	(88,535)
Income on equity method investments	10	7	18	17
INCOME FROM CONTINUING OPERATIONS	99,825	51,428	196,273	107,116
(LOSS) INCOME FROM DISCONTINUED OPERATIONS, NET OF INCOME TAX PROVISION (BENEFIT) OF $3, $5,101, $(19) AND $3,171, RESPECTIVELY	(6)	5,060	29	8,130
NET INCOME	99,819	56,488	196,302	115,246
Net income attributable to noncontrolling interest	(154)	(199)	(319)	(356)
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION	$ 99,665	$ 56,289	$ 195,983	$ 114,890
BASIC:
Income from continuing operations attributable to American Tower Corporation	$ 0.25	$ 0.13	$ 0.49	$ 0.27
Income from discontinued operations attributable to American Tower Corporation		$ 0.01		$ 0.02
Net income attributable to American Tower Corporation	$ 0.25	$ 0.14	$ 0.49	$ 0.29
DILUTED:
Income from continuing operations attributable to American Tower Corporation	$ 0.25	$ 0.13	$ 0.48	$ 0.26
Income from discontinued operations attributable to American Tower Corporation		$ 0.01		$ 0.02
Net income attributable to American Tower Corporation	$ 0.25	$ 0.14	$ 0.48	$ 0.28
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
BASIC	402,733	397,418	402,540	397,300
DILUTED	405,024	408,832	405,685	408,855

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2010	Jun. 30, 2009
Stock-based compensation expense	$ 13,228	$ 12,836	$ 26,792	$ 37,174
Interest income, TV Azteca, interest expense	372	372	744	744
Income From Discontinued Operations, Income Tax Provision (Benefit)	$ 3	$ 5,101	$ (19)	$ 3,171

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2010	Jun. 30, 2009
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 196,302	$ 115,246
Adjustments to reconcile net income to cash provided by operating activities:
Stock-based compensation expense	26,792	37,174
Depreciation, amortization and accretion	221,238	202,331
Deferred income taxes related to discontinued operations	0	(3,171)
Other non-cash items reflected in statements of operations	74,843	89,084
Increase in net deferred rent asset	(19,276)	(5,334)
Increase in restricted cash	(7,655)	1,829
Increase in assets	(33,889)	(31,553)
Increase in liabilities	58,041	3,740
Cash provided by operating activities	516,396	409,346
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments for purchase of property and equipment and construction activities	(132,510)	(113,854)
Payments for acquisitions	(132,472)	(93,266)
Proceeds from sale of available-for-sale securities and other long-term assets	2,131	2,395
Deposits, restricted cash, investments and other	(24,059)	(7,056)
Cash used for investing activities	(286,910)	(211,781)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of senior debt		300,000
Borrowings under credit facilities	75,000
Repayments of notes payable, credit facilities and capital leases	(139,060)	(257,484)
Purchases of Class A common stock	(200,531)	(65,745)
Proceeds from stock options, warrants and stock purchase plan	90,079	16,101
Deferred financing costs and other financing activities	(351)	(9,719)
Cash used for financing activities	(174,863)	(16,847)
Net effect of changes in foreign currency exchange rates on cash and cash equivalents	977	(158)
NET INCREASE IN CASH AND CASH EQUIVALENTS	55,600	180,560
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	247,293	143,077
CASH AND CASH EQUIVALENTS, END OF PERIOD	302,893	323,637
CASH PAID FOR INCOME TAXES	11,257	18,996
CASH PAID FOR INTEREST	$ 109,925	$ 119,881

CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS EQUITY (USD $) In Thousands, except Share data	Total	Class A Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Noncontrolling Interest	Total Comprehensive Income (Loss)
BALANCE at Dec. 31, 2008	$ 2,994,479	$ 4,685	$ 8,109,224	$ (2,746,429)	$ (20,031)	$ (2,356,127)	$ 3,157
BALANCE (shares) at Dec. 31, 2008		468,513,843		(71,536,947)
Share based compensation related activity (shares)		1,062,730
Share based compensation related activity	49,592	12	49,580
Issuance of vested restricted stock, net of employee withholdings tax (shares)
Issuance of vested restricted stock, net of employee withholdings tax
Issuance of common stock upon exercise of warrants (shares)		22,612
Issuance of common stock upon exercise of warrants	99		99
Issuance of common stock-Stock Purchase Plan (shares)		46,639
Issuance of common stock-Stock Purchase Plan	1,008		1,008
Treasury stock activity (shares)				(2,298,970)
Treasury stock activity	(69,631)			(69,631)
Net change in fair value of cash flow hedges, net of tax	2,029				2,029			2,029
Net realized gain on cash flow hedges, net of tax	60				60			60
Net unrealized loss on available-for-sale securities, net of tax	83				83			83
Convertible notes exchanged for common stock (in Shares)		96
Convertible notes exchanged for common stock	2		2					2
Foreign currency translation adjustment, net of tax	(1,673)				(1,673)			(1,673)
Distributions to noncontrolling interest	(259)						(259)
Net income	115,246					114,890	356	115,246
Total comprehensive income								115,747
BALANCE at Jun. 30, 2009	3,091,035	4,697	8,159,913	(2,816,060)	(19,352)	(2,241,237)	3,254
BALANCE (shares) at Jun. 30, 2009		469,645,920		(73,835,917)
BALANCE at Dec. 31, 2009	3,318,125	4,797	8,393,643	(2,961,177)	(12,649)	(2,109,532)	3,043
BALANCE (shares) at Dec. 31, 2009		479,703,633		(78,106,649)
Share based compensation related activity (shares)		2,729,388
Share based compensation related activity	108,458	28	108,430
Issuance of vested restricted stock, net of employee withholdings tax (shares)		387,615
Issuance of vested restricted stock, net of employee withholdings tax	(7,187)	4	(7,191)
Issuance of common stock upon exercise of warrants (shares)		1,631,061
Issuance of common stock upon exercise of warrants	6,859	16	6,843
Issuance of common stock-Stock Purchase Plan (shares)		38,542
Issuance of common stock-Stock Purchase Plan	1,327		1,327
Treasury stock activity (shares)				(4,638,487)
Treasury stock activity	(196,343)			(196,343)
Net change in fair value of cash flow hedges, net of tax	4,602				4,602			4,602
Net realized gain on cash flow hedges, net of tax	59				59			59
Net unrealized loss on available-for-sale securities, net of tax	13				13			13
Foreign currency translation adjustment, net of tax	(1,854)				(1,854)			(1,854)
Distributions to noncontrolling interest	(351)						(351)
Net income	196,302					195,983	319	196,302
Total comprehensive income								199,122
BALANCE at Jun. 30, 2010	$ 3,430,010	$ 4,845	$ 8,503,052	$ (3,157,520)	$ (9,829)	$ (1,913,549)	$ 3,011
BALANCE (shares) at Jun. 30, 2010		484,490,239		(82,745,136)

Description of Business, Basis of Presentation and Accounting Policies

6 Months Ended

Jun. 30, 2010

Description of Business, Basis of Presentation and Accounting Policies

1.	Description of Business, Basis of Presentation and Accounting Policies

American Tower Corporation is, together with its subsidiaries (collectively, "ATC" or the "Company"), an independent developer, owner and operator of wireless and broadcast communications sites in the United States, Mexico, Brazil, India and Chile. The Company's primary business is the leasing of antenna space on multi-tenant communications sites to wireless service providers and radio and television broadcast companies. The Company also manages rooftop and tower sites for property owners, operates in-building and outdoor distributed antenna system ("DAS") networks, and provides network development services that primarily support its rental and management operations and the addition of new tenants and equipment on its sites.

ATC is a holding company that conducts its operations through its directly and indirectly owned subsidiaries. ATC's principal United States operating subsidiaries are American Towers, Inc. ("ATI") and SpectraSite Communications, LLC ("SpectraSite"). ATC conducts its international operations through its subsidiary, American Tower International, Inc., which in turn conducts operations through its various international operating subsidiaries. The Company's international operations consist of its operations in Mexico, Brazil, India and, more recently, Chile.

The accompanying condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC"). The financial information included herein is unaudited; however, the Company believes that all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair presentation of the Company's financial position and results of operations for such periods have been included. Results of interim periods may not be indicative of results for the full year. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued as additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated up to the date of issuance of these financial statements. These condensed consolidated financial statements and related notes should be read in conjunction with the Company's Annual Report on Form 10-K for the year ended December 31, 2009.

Significant Accounting Policies and Use of Estimates—The preparation of financial statements in conformity with accounting principles generally accepted in the United States ("GAAP") requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results may differ from those estimates, and such differences could be material to the accompanying condensed consolidated financial statements.

Concentrations of Credit Risk—The Company is subject to concentrations of credit risk related to its cash and cash equivalents, notes receivable, trade receivables, deferred rent asset and derivative instruments. The Company mitigates its risk with respect to cash and cash equivalents and derivative instruments by maintaining its deposits and contracts at high quality financial institutions and monitoring the credit ratings of those institutions.

The Company mitigates its concentrations of credit risk with respect to notes and trade receivables by actively monitoring the creditworthiness of its borrowers and customers. The Company derives the largest portion of its revenues, corresponding trade receivables and the related deferred rent asset from a small number of customers in the telecommunications industry, and as of June 30, 2010, approximately 60% of its revenues are derived from four customers in the United States, whose combined accounts receivable, net and deferred rent asset are $16.7 million and $286.4 million, respectively.

As of June 30, 2010, current and long-term accounts receivable, net and related assets (which include financing lease commitments and a deferred rent asset that are primarily long-term in nature) included $16.7 million (net of reserves, allowances and value added tax) and $45.2 million, respectively, for our largest foreign customer, Grupo Iusacell, which represented approximately 4% of the Company's total revenues for the six months ended June 30, 2010. Grupo Iusacell has been engaged in a restructuring of its U.S. Dollar denominated debt since the first quarter of 2009, and has periodically made partial payments to the Company since that time. Effective April 1, 2010, the Company renegotiated its agreements with Grupo Iusacell to include, among other changes, the conversion of approximately $18.3 million of accounts receivable, net, and associated value added tax, to a long-term, interest bearing receivable to be repaid over five years.

Foreign Currency—As a result of changes to the organizational structure of the Company's subsidiaries in Latin America in 2010, the Company has determined that effective January 1, 2010, the functional currency of its foreign subsidiary in Brazil is the Brazilian Real. From that point forward, all assets and liabilities held by the subsidiary in Brazil are translated into U.S. Dollars at the exchange rate in effect at the end of the applicable reporting period. Revenues and expenses are translated at the average monthly exchange rates and the cumulative translation effect is included in stockholders' equity. The change in functional currency from U.S. Dollars to Brazilian Real gave rise to an increase in the net value of certain non-monetary assets and liabilities. The aggregate impact on such assets and liabilities was $38.1 million with an offsetting increase in accumulated other comprehensive income (loss).

As a result of the renegotiation of the Company's agreements with Grupo Iusacell, which included, among other changes, converting all of Grupo Iusacell's contractual obligations to the Company from U.S. Dollars to Mexican Pesos, the Company has determined that effective April 1, 2010, the functional currency of certain of its foreign subsidiaries in Mexico is the Mexican Peso. From that point forward, all assets and liabilities held by those subsidiaries in Mexico are translated into U.S. Dollars at the exchange rate in effect at the end of the applicable reporting period. Revenues and expenses are translated at the average monthly exchange rates and the cumulative translation effect is included in stockholders' equity. The change in functional currency from U.S. Dollars to Mexican Pesos gave rise to a decrease in the net value of certain non-monetary assets and liabilities. The aggregate impact on such assets and liabilities was $37.6 million with an offsetting decrease in accumulated other comprehensive income (loss).

Recently Adopted Accounting Standards—In January 2010, the Financial Accounting Standards Board ("FASB") issued guidance clarifying existing disclosure requirements and adding disclosure requirements with respect to fair value measurements. This guidance was effective for the Company as of January 1, 2010 and had no impact on its consolidated results of operations or financial position.

Accounting Standards Updates—In October 2009, the FASB issued new guidance which establishes accounting and reporting guidance for arrangements including multiple revenue-generating activities. This guidance requires companies to allocate the overall consideration to each deliverable under the arrangement using the estimated selling prices in the absence of vendor specific objective evidence or third-party evidence of selling price for deliverables. This guidance is effective for any contracts entered into, or materially modified by, the Company after January 1, 2011, with early adoption available. The Company is evaluating the impact, if any, that this update will have on its condensed consolidated results of operations and financial position.

Short-Term Investments and Available-For-Sale Securities

6 Months Ended

Jun. 30, 2010

Short-Term Investments and Available-For-Sale Securities

2.	Short-Term Investments and Available-For-Sale Securities

As of June 30, 2010, short-term investments and available-for-sale securities included Brazilian Treasury securities of $27.7 million, whose original maturities were in excess of three months, and $0.2 million of available-for-sale securities.

- Definition

This item represents the entire disclosure related to Investments in Certain Debt and Equity Securities (and certain other trading assets) which include all debt and equity securities (other than those equity securities accounted for under the equity or cost methods of accounting) with readily determinable fair values. Other trading assets include assets that are carried on the balance sheet at fair value and held for trading purposes. A debt security represents a creditor relationship with an enterprise that is in the form of a security. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities (and other trading assets).

+ References+ Details

Goodwill and Other Intangible Assets

6 Months Ended

Jun. 30, 2010

Goodwill and Other Intangible Assets

3.	Goodwill and Other Intangible Assets

The changes in the carrying value of goodwill for the six months ended June 30, 2010 are as follows (in thousands):


Balance as of December 31, 2009 as adjusted for purchase accounting measurement period of adjustments	$	2,255,234
Effect of foreign currency translation		709

Balance as of June 30, 2010	$	2,255,943

The Company's other intangible assets subject to amortization consist of the following:


	Estimated Useful Lives	June 30, 2010			December 31, 2009 (3)
	(years)	(in thousands)
Acquired network location (1)	20	$	1,129,845		$	1,106,498
Acquired customer base	15-20		752,276			756,928
Acquired customer relationship	20		939,715			878,117
Acquired licenses and other intangibles	5-15		21,574			21,574
Economic Rights, TV Azteca	70		30,292			30,292

Total			2,873,702			2,793,409
Less accumulated amortization			(1,316,392	)		(1,238,579	)

Intangible assets, net			1,557,310			1,554,830
Deferred financing costs, net (2)	N/A		39,182			43,695

Other intangible assets, net		$	1,596,492		$	1,598,525

(1)	Acquired network location intangibles are amortized over the shorter of the term of the corresponding ground lease or 20 years, as the Company considers these intangibles to be directly related to the tower assets.

(2)	Deferred financing costs are amortized over the term of the respective debt instruments to which they relate. This amortization is included in interest expense, rather than in amortization expense.

(3)	December 31, 2009 balances have been revised to reflect purchase accounting adjustments.

The Company amortizes these intangibles on a straight-line basis. As of June 30, 2010, the remaining weighted average amortization period of the Company's intangible assets, excluding the TV Azteca Economic Rights detailed in note 4 to the Company's consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2009, was approximately 10 years. Amortization of intangible assets for the three and six months ended June 30, 2010 was approximately $37.6 million and $75.4 million (excluding amortization of deferred financing costs, which is included in interest expense), respectively. Amortization of intangible assets for the three and six months ended June 30, 2009 was approximately $35.9 million and $68.0 million (excluding amortization of deferred financing costs, which is included in interest expense), respectively.

- Definition

Discloses the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain or loss on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss. This element may be used as a single block of text to include the entire intangible asset disclosure including data and tables.

+ References+ Details

Financing Transactions

6 Months Ended

Jun. 30, 2010

Financing Transactions

4.	Financing Transactions

Revolving Credit Facility and Term Loan—As of June 30, 2010, the Company had $625.0 million outstanding under its $1.25 billion senior unsecured revolving credit facility ("Revolving Credit Facility") and had approximately $3.1 million of undrawn letters of credit outstanding. In March 2008, the Company increased its borrowing capacity under the Revolving Credit Facility by adding $325.0 million of term loan commitments ("Term Loan"). As of June 30, 2010, the Term Loan was fully drawn. The Company continues to maintain the ability to draw down and repay amounts under the Revolving Credit Facility in the ordinary course.

XCEL Credit Facility—At the time of the Company's acquisition of XCEL Telecom Private Limited ("XCEL") on May 27, 2009, a 4.8 billion Indian Rupee-denominated credit facility ("XCEL Credit Facility") was in place, of which 3.4 billion Indian Rupees (approximately $77.3 million) was outstanding. In April 2010, the Company repaid all of the outstanding indebtedness incurred under the XCEL Credit Facility and terminated the XCEL Credit Facility upon repayment.

Stock Repurchase Program—During the six months ended June 30, 2010, the Company repurchased an aggregate of 4.6 million shares of its Class A common stock ("Common Stock") for an aggregate of $196.3 million, including commissions and fees, pursuant to its $1.5 billion stock repurchase program approved by the Company's Board of Directors in February 2008 ("2008 Buyback"). Between July 1, 2010 and July 23, 2010, the Company repurchased a total of 879,700 shares of its Common Stock for an aggregate of $40.0 million, including commissions and fees. As of July 23, 2010, the Company had repurchased a total of 26.1 million shares of Common Stock for an aggregate of $984.4 million, including commissions and fees, pursuant to the 2008 Buyback.

Under the 2008 Buyback, the Company is authorized to purchase shares from time to time through open market purchases or privately negotiated transactions at prevailing prices in accordance with securities laws and other legal requirements, and subject to market conditions and other factors. To facilitate repurchases, the Company purchases its Common Stock pursuant to trading plans under Rule 10b5-1 of the Securities Exchange Act of 1934, as amended, which allows the Company to repurchase shares during periods when it otherwise might be prevented from doing so under insider trading laws or because of self-imposed trading blackout periods. In the near term, the Company expects to fund any further repurchases of its Common Stock through a combination of cash on hand, cash generated by operations and borrowings under its Revolving Credit Facility. Purchases under the 2008 Buyback are subject to the Company having available cash to fund repurchases.

Derivative Financial Instruments

6 Months Ended

Jun. 30, 2010

Derivative Financial Instruments

5.	Derivative Financial Instruments

The Company is exposed to certain risks related to its ongoing business operations. The primary risk managed through the use of derivative instruments is interest rate risk. The Company enters into interest rate protection agreements to manage exposure on the variable rate debt under its credit facilities and to manage variability in cash flows relating to forecasted interest payments. Under these agreements, the Company is exposed to credit risk to the extent that a counterparty fails to meet the terms of a contract. The Company's credit risk exposure is limited to the current value of the contract at the time the counterparty fails to perform. The Company believes its contracts as of June 30, 2010 are with creditworthy institutions.

If a derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are recorded in accumulated other comprehensive income (loss) and are recognized in the results of operations when the hedged item affects earnings. Ineffective portions of changes in the fair value of cash flow hedges are recognized immediately in the results of operations. For derivative instruments not designated as hedging instruments, changes in fair value are recognized in the results of operations in the period in which the change occurs.

As of June 30, 2010, the Company held thirteen interest rate swap agreements, all of which have been designated as cash flow hedges, and which have an aggregate notional amount of $625.0 million, interest rates ranging from 2.86% to 4.08% and expiration dates through March 2011. The Company utilizes these interest rate swap agreements to manage its exposure to variability in cash flows relating to forecasted interest payments under its Revolving Credit Facility and Term Loan. As of June 30, 2010 and December 31, 2009, the carrying amounts of the Company's derivative financial instruments, along with the estimated fair values of the related liabilities are as follows (in thousands):


As of June 30, 2010	Balance Sheet Location	Notional Amount		Carrying Amount and Fair Value
Liabilities:
Interest rate swap agreements	Other long-term liabilities	$	625,000	$	11,321

As of December 31, 2009	Balance Sheet Location	Notional Amount		Carrying Amount and Fair Value
Liabilities:
Interest rate swap agreements	Other long-term liabilities	$	625,000	$	18,852

During the six months ended June 30, 2010 and 2009, the interest rate swap agreements held by the Company had the following impact on other comprehensive income ("OCI") included in the condensed consolidated balance sheet and in the condensed consolidated statement of operations (in thousands):


Six Months Ended June 30, 2010
Amount of Gain/(Loss) Recognized in OCI on Derivatives (Effective Portion)	Location of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Amount of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Location of Gain/ (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Gain/(Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)
$(4,771)	Interest expense	$(9,373)	N/A	N/A

Six Months Ended June 30, 2009
Amount of Gain/(Loss) Recognized in OCI on Derivatives (Effective Portion)	Location of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Amount of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Location of Gain/ (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Gain/(Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)
$(9,678)	Interest expense	$(7,649)	N/A	N/A

Fair Value Measurements

6 Months Ended

Jun. 30, 2010

Fair Value Measurements

6.	Fair Value Measurements

The Company determines the fair market values of its financial instruments based on the fair value hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Below are the three levels of inputs that may be used to measure fair value:


Level 1		Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2		Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3		Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Items Measured at Fair Value on a Recurring Basis—The fair value of the Company's financial assets and liabilities that are required to be measured on a recurring basis at fair value is as follows:


	June 30, 2010
	Fair Value Measurements Using					Assets/Liabilities at Fair Value
	Level 1		Level 2		Level 3	Assets/Liabilities at Fair Value
	(in thousands)
Assets:
Short-term investments and available-for-sale securities (1)	$	27,891				$	27,891
Liabilities:
Interest rate swap agreements (2)			$	11,321		$	11,321

	December 31, 2009
	Fair Value Measurements Using					Assets/Liabilities at Fair Value
	Level 1		Level 2		Level 3	Assets/Liabilities at Fair Value
	(in thousands)
Assets:
Short-term investments and available-for-sale securities (1)	$	9,776				$	9,776
Liabilities:
Interest rate swap agreements (2)			$	18,852		$	18,852

(1)	Consists of available-for-sale securities traded on active markets as well as certain Brazilian Treasury securities that are highly liquid and actively traded in over-the-counter markets.

(2)	Consists of interest rate swap agreements based on the London Interbank Offering Rate ("LIBOR") whose value is determined using a pricing model with inputs that are observable in the market or can be derived principally from, or corroborated by, observable market data.

The fair value of the Company's interest rate swap agreements recorded as liabilities is included in other long-term liabilities in the accompanying condensed consolidated balance sheet as of June 30, 2010. Fair valuations of the Company's interest rate swap agreements reflect the value of the instrument including the values associated with counterparty risk and the Company's own credit standing. The Company includes in the valuation of the derivative instrument the value of the net credit differential between the counterparties to the derivative contract.

Items Measured at Fair Value on a Nonrecurring Basis—The Company's notes receivable and other long-term assets, long-lived assets, intangibles and goodwill are measured at fair value on a nonrecurring basis. During the six months ended June 30, 2010, the Company did not record any significant changes to the fair value of these assets as a result of an impairment, using level 3 inputs, on a nonrecurring basis.

Fair Value of Financial Instruments—The carrying value of the Company's financial instruments, with the exception of long-term obligations, including current portion, reasonably approximate the related fair values as of June 30, 2010 and December 31, 2009. The Company's estimates of fair value of its long-term obligations, including current portion, are based primarily upon reported market values. As of June 30, 2010, the carrying value and fair value of long-term obligations, including current portion, were $4.2 billion and $4.3 billion, respectively. As of December 31, 2009, the carrying value and fair value of long-term obligations, including current portion, were $4.2 billion and $4.3 billion, respectively.

- Definition

This item represents the complete disclosure regarding the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the Company is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risk is are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References+ Details

Income Taxes

6 Months Ended

Jun. 30, 2010

Income Taxes

7.	Income Taxes

The Company provides for income taxes at the end of each interim period based on the estimated effective tax rate for the full fiscal year. Cumulative adjustments to the Company's estimate are recorded in the interim period in which a change in the estimated annual effective rate is determined.

As of June 30, 2010, the Company had unrecognized tax benefits of $76.3 million, of which approximately $35.7 million would impact discontinued operations, if recognized. The total amount that would affect the effective tax rate, if recognized, was $32.6 million, net of deferred tax assets of $8.0 million. The Company expects the unrecognized tax benefits to change over the next 12 months if certain tax matters ultimately settle with the applicable taxing jurisdiction during this timeframe, as described in note 11 to the Company's consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2009. The impact of the amount of such changes to previously recorded uncertain tax positions could range from zero to $2.0 million. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands):


Balance at January 1, 2010	$	87,975
Additions based on tax positions related to the current year		10,158
Additions for tax positions of prior year		8,948
Reductions for tax positions of prior years		(30,855	)
Foreign currency		146
Reduction as a result of the lapse of statute limitations		(53	)

Balance at June 30, 2010	$	76,319

The Company recorded penalties and tax-related interest expense during the three and six months ended June 30, 2010 of $0.7 million and $1.4 million, respectively. As of June 30, 2010 and December 31, 2009, the total amount of accrued income tax-related interest and penalties included in other long-term liabilities in the condensed consolidated balance sheets was $16.8 million and $15.2 million, respectively.

In an effort to efficiently fund Latin American operations, during the first quarter of 2010, the Company reorganized an existing financing entity, which resulted in a reversal of $32.6 million of accrued income tax liabilities which was recognized in the condensed consolidated statement of operations.

During the six months ended June 30, 2010, the Company performed additional analysis of its net operating losses, resulting in recognition of $26.3 million of previously unrecognized net operating losses in the condensed consolidated statements of operations. In addition, the Company also recorded additional tax reserves of $19.1 million.

The Company files numerous consolidated and separate income tax returns, including U.S. federal and state tax returns and foreign tax returns. The Company may be subject to examinations in various jurisdictions for certain tax years. As a result of the Company's ability to carry forward federal and state net operating losses, the applicable tax years remain open to examination until three years after the applicable loss carry forwards have been used or expired.

Stock-Based Compensation

6 Months Ended

Jun. 30, 2010

Stock-Based Compensation

8.	Stock-Based Compensation

The Company recognized non-cash stock-based compensation expense during the three and six months ended June 30, 2010 of approximately $13.2 million and $26.8 million, respectively, and non-cash stock-based compensation expense during the three and six months ended June 30, 2009 of approximately $12.8 million and $37.2 million, respectively. Stock-based compensation expense for the six months ended June 30, 2009 includes $6.6 million related to the modification of the vesting and exercise terms for a certain employee's equity awards. The Company did not capitalize any stock-based compensation during the six months ended June 30, 2010 and 2009.

Stock Options—During the six months ended June 30, 2010, the Company granted stock options to purchase 1.1 million shares of its Common Stock pursuant to its 2007 Equity Incentive Plan ("2007 Plan").

The following table summarizes the Company's option activity for the six months ended June 30, 2010:


	Number of Options
Outstanding as of January 1, 2010	11,434,178
Granted	1,066,845
Exercised	(2,729,388	)
Forfeited	(129,459	)
Expired	(24,640	)

Outstanding as of June 30, 2010	9,617,536

The Company estimates the fair value of each option grant on the date of grant using the Black-Scholes option pricing model. The following assumptions were used to determine the grant date fair value for options granted during the six months ended June 30, 2010:


Range of risk-free interest rate		1.90% - 2.39%
Weighted average risk-free interest rate		2.38%
Expected life of option grants		4.6
Range of expected volatility of underlying stock price		37.11% - 37.30%
Weighted average expected volatility of underlying stock price		37.13%
Expected annual dividends		N/A

The weighted average grant date fair value per share during the six months ended June 30, 2010 was $14.97. As of June 30, 2010, total unrecognized compensation expense related to unvested stock options was $40.8 million, and is expected to be recognized over a weighted average period of approximately two years.

Restricted Stock Units—During the six months ended June 30, 2010, the Company granted restricted stock units with respect to 0.9 million shares of its Common Stock pursuant to the 2007 Plan.

The following table summarizes the Company's restricted stock unit activity during the six months ended June 30, 2010:


	Number of Units
Outstanding as of January 1, 2010	2,026,032
Granted	889,610
Vested	(552,564	)
Forfeited	(65,925	)

Outstanding as of June 30, 2010	2,297,153

As of June 30, 2010, total unrecognized compensation expense related to unvested restricted stock units granted under the 2007 Plan was $70.8 million, and is expected to be recognized over a weighted average period of approximately three years.

Employee Stock Purchase Plan—The Company maintains an employee stock purchase plan ("ESPP") for all eligible employees as described in note 12 to the Company's Annual Report on Form 10-K for the year ended December 31, 2009. The offering periods run from June 1 through November 30 and from December 1 through May 31 of each year. During the six months ended June 30, 2010, employees purchased 38,542 shares under the ESPP and the fair value of such shares was $9.51.

Key assumptions used to apply the Black-Scholes pricing model for shares purchased through the ESPP during the six months ended June 30, 2010 are as follows:


Approximate risk-free interest rate		0.22%
Expected life of shares		6 months
Expected volatility of underlying stock price		35.27%
Expected annual dividends		N/A

Earnings per Common Share

6 Months Ended

Jun. 30, 2010

Earnings per Common Share

9.	Earnings per Common Share

Basic income from continuing operations per common share represents income from continuing operations attributable to American Tower Corporation divided by the weighted average number of common shares outstanding during the period. Diluted income from continuing operations per common share represents income from continuing operations attributable to American Tower Corporation divided by the weighted average number of common shares outstanding during the period and any dilutive common share equivalents, including shares issuable upon exercise of stock options and warrants as determined under the treasury stock method and upon conversion of the Company's convertible notes, as determined under the if-converted method.

The following table sets forth basic and diluted income from continuing operations per common share computational data for the three and six months ended June 30, 2010 and 2009 (in thousands, except per share data):


	Three Months Ended June 30,				Six Months Ended June 30,
	2010		2009		2010		2009
Income from continuing operations attributable to American Tower Corporation	$	99,671	$	51,229	$	195,954	$	106,760

Effect of convertible notes		—		747		—		1,494

Income available to common shareholders, as adjusted for diluted earnings	$	99,671	$	51,976	$	195,954	$	108,254

Basic weighted average common shares outstanding		402,733		397,418		402,540		397,300
Dilutive securities:
Stock options, warrants and convertible notes		2,291		11,414		3,145		11,555

Diluted weighted average common shares outstanding		405,024		408,832		405,685		408,855

Basic income from continuing operations attributable to American Tower Corporation per common share	$	0.25	$	0.13	$	0.49	$	0.27

Diluted income from continuing operations attributable to American Tower Corporation per common share	$	0.25	$	0.13	$	0.48	$	0.26

For the three and six months ended June 30, 2010, the weighted average number of common shares outstanding excludes shares issuable upon conversion of the Company's convertible notes of zero and 0.3 million, respectively, and shares issuable upon exercise of the Company's stock options and share based awards of 3.4 million and 1.9 million, respectively, as the effect would be anti-dilutive. For the three and six months ended June 30, 2009, the weighted average number of common shares outstanding excludes shares issuable upon conversion of the Company's convertible notes of 1.2 million, and shares issuable upon exercise of the Company's stock options and share based awards of 10.3 million and 10.4 million, respectively, as the effect would be anti-dilutive.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2010

Commitments and Contingencies

10.

Commitments and Contingencies

Legal and Governmental Proceedings Related to Review of Stock Option Granting Practices and Related Accounting—During the year ended December 31, 2006, the Company received a letter of informal inquiry from the SEC Division of Enforcement, a subpoena from the United States Attorney's Office for the Eastern District of New York, and an Information Document Request from the Internal Revenue Service ("IRS"), each requesting documents and other information related to Company stock option grants and stock option practices. In addition, in August 2007, the Company received a request for information from the Department of Labor ("DOL") with respect to the Company's retirement savings plan, including documents related to Company stock option grants and the Company's historical stock option administrative practices. The Company has also become aware that a former officer of the Company has received a "Wells" notice from the SEC, which affords such individual the opportunity to make a submission to the SEC with respect to contemplated civil enforcement recommendations against such individual for certain violations of the federal securities laws. In September 2008, the DOL concluded its review and advised the Company that no action would be taken. The reviews being conducted by the SEC, the U.S. Attorney's Office and the IRS remain ongoing, and the Company continues to cooperate on these matters.

Mexico Litigation—One of the Company's subsidiaries, SpectraSite Communications, Inc. ("SCI"), is involved in a lawsuit brought in Mexico against a former Mexican subsidiary of SCI (the subsidiary of SCI was sold in 2002, prior to the Company's merger of a newly formed, wholly owned subsidiary with SCI's parent in 2005). The lawsuit concerns a terminated tower construction contract and related agreements with a wireless carrier in Mexico. The primary issue for the Company is whether SCI itself can be found liable to the Mexican carrier. The trial and lower appellate courts initially found that SCI had no such liability in part because Mexican courts do not have full jurisdiction over SCI. These decisions were appealed by the plaintiff, and in July 2008, they were reversed by an intermediate Mexican appellate court. In its decision, the intermediate appellate court identified potential damages of approximately $23.0 million. SCI appealed that ruling to a higher constitutional court in Mexico. In January 2009, the constitutional court ruled in SCI's favor, remanding the case back to the intermediate appellate court for further proceedings. In March 2009, the intermediate appellate court issued its decision, which reasserts jurisdiction and reimposes liability on SCI. In April 2009, as permitted under Mexican law, SCI filed an appeal of this decision to the higher constitutional court, on the grounds that the decision of the intermediate appellate court is inconsistent with the January 2009 ruling of the higher constitutional court and Mexican law. In August 2009, the plaintiff filed a petition with the Supreme Court of Mexico asking the court to rule on SCI's appeal to the constitutional court. In September 2009, the Supreme Court refused to hear the appeal. As a result, the case remains pending in the constitutional court and should be listed for final resolution in August 2010. The Company is unable to estimate its share, if any, of potential liability until final resolution is officially published.

AT&T Transaction—SpectraSite entered into an agreement with SBC Communications Inc., a predecessor entity to AT&T Inc. ("AT&T"), for the lease or sublease of approximately 2,500 towers from AT&T between December 2000 and August 2004. All of the towers are part of the Company's securitization transaction. The average term of the lease or sublease for all sites at the inception of the agreement was approximately 27 years, assuming renewals or extensions of the underlying ground leases for the sites. SpectraSite has the option to purchase the sites subject to the applicable lease or sublease upon its expiration. Each tower is assigned to an annual tranche, ranging from 2013 to 2032, which represents the outside expiration date for the sublease rights to that tower. The purchase price for each site is a fixed amount stated in the sublease for that site plus the fair market value of certain alterations made to the related tower by AT&T. The aggregate purchase option price for the towers leased and subleased was approximately $432.8 million as of June 30, 2010, and will accrete at a rate of 10% per year to the applicable expiration of the lease or sublease of a site. For all such sites purchased by SpectraSite, AT&T has the right to continue to lease the reserved space for successive one year terms at a rent equal to the lesser of the agreed upon market rate and the then current monthly fee, which is subject to an annual increase based on changes in the Consumer Price Index.

ALLTEL Transaction—In December 2000, the Company entered into an agreement with ALLTEL (which completed its merger with Verizon Wireless in January 2009) to acquire towers from ALLTEL through a 15-year sublease agreement. Pursuant to the agreement with ALLTEL, as amended, the Company acquired rights to a total of approximately 1,800 towers in tranches between April 2001 and March 2002. The Company has the option to purchase each tower at the expiration of the applicable sublease, which will occur in tranches between April 2016 and March 2017 based on the original closing date for such tranche of towers. The purchase price per tower as of the original closing date was $27,500 and will accrete at a rate of 3% per annum through the expiration of the applicable sublease. The aggregate purchase option price for the subleased towers was approximately $64.2 million as of June 30, 2010. At ALLTEL's option, at the expiration of the sublease, the purchase price would be payable in cash or with 769 shares of the Company's Common Stock per tower.

XCEL Litigation—On June 3, 2010, Horse-Shoe Capital ("Horse-Shoe"), a company formed under the laws of the Republic of Mauritius, filed a complaint in the Supreme Court of the State of New York, New York County, with respect to Horse-Shoe's sale of XCEL to American Tower Mauritius ("AT Mauritius"), our wholly-owned subsidiary formed under the laws of the Republic of Mauritius. The complaint names AT Mauritius, ATI and the Company as defendants, and the dispute concerns the timing and amount of distributions to be made by AT Mauritius to Horse-Shoe from a $7.5 million holdback escrow account and a $15.7 million tax escrow account, each established by the transaction agreements at the closing of the transaction. The complaint seeks release of the entire holdback escrow account, plus an additional $2.8 million, as well as the release of approximately $12.0 million of the tax escrow account. The complaint also seeks punitive damages in excess of $69 million. The Company expects to file an answer to the complaint in August 2010, disputing both the amounts alleged to be owed under the escrow agreements as well as the timing of the escrow distributions. The Company also will assert in its answer that the demand for punitive damages is meritless. The Company intends to defend the lawsuit vigorously.

Litigation—The Company periodically becomes involved in various claims and lawsuits that are incidental to its business. In the opinion of Company management, after consultation with counsel, other than the legal proceedings discussed above, there are no matters currently pending that would, in the event of an adverse outcome, materially impact the Company's consolidated financial position, results of operations or liquidity.

Acquisitions

6 Months Ended

Jun. 30, 2010

Acquisitions

11.

Acquisitions

XCEL Acquisition—On May 27, 2009, the Company acquired 100% of the outstanding common and preferred stock of XCEL. This acquisition had a purchase price, after certain post-closing adjustments, of $98.0 million. During the three months ended June 30, 2010, the Company finalized the purchase accounting for this acquisition. The preliminary purchase price was allocated to the acquired assets and liabilities based on the estimated fair value of the acquired assets and liabilities at the date of acquisition, subject to subsequent adjustments as the preliminary estimates of the fair value of assets and liabilities and estimated purchase price were finalized.

The following table summarizes the aggregate purchase consideration paid and the amounts of assets and liabilities acquired at the acquisition date (in thousands), the adjustments to which are reflected in the Company's condensed consolidated balance sheet for the year ended December 31, 2009:


	Final Purchase Price Allocation			Preliminary Purchase Price Allocation
Current and non-current assets	$	59,612		$	59,612
Property and equipment		83,523			83,523
Intangible assets (1)		38,091			38,091
Current and other long-term liabilities		(135,824	)		(135,824	)

Fair value of net assets acquired	$	45,402		$	45,402

Goodwill (2)		52,631			50,641

(1)	Consists of customer relationships of approximately $18.3 million and network location of approximately $19.8 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is not expected to be deductible for local income tax purposes. The goodwill was allocated to the rental and management segment.

Insight Acquisition—On October 28, 2009, the Company acquired 100% of the outstanding stock of Insight Infrastructure Pte. Ltd. ("Insight"), a company formed under the laws of Singapore, and the parent company of Transcend Infrastructure Limited, a company formed under the laws of India. This acquisition had a final purchase price, after certain post-closing adjustments, of $19.3 million. During the three months ended June 30, 2010, the Company finalized the purchase accounting for this acquisition. The preliminary purchase price was allocated to the acquired assets and liabilities based on the estimated fair value of the acquired assets and liabilities at the date of acquisition, subject to subsequent adjustments as the preliminary estimates of purchase price and the fair value of the assets and liabilities were finalized.


	Final Purchase Price Allocation			Preliminary Purchase Price Allocation
Current and non-current assets	$	3,513		$	3,552
Property and equipment		19,625			19,625
Intangible assets (1)		2,709			4,408
Current and other long-term liabilities		(8,116	)		(8,694	)

Fair value of net assets acquired	$	17,731		$	18,891

Goodwill (2)		1,617			22

(1)	Consists of customer relationships of approximately $0.9 million and network location of approximately $1.8 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is not expected to be deductible for local income tax purposes. The goodwill was allocated to the rental and management segment.

Brazil Acquisition—On July 22, 2009, the Company completed its acquisition of 230 towers and related third party leases located in Brazil for an aggregate purchase price of $51.3 million, which consisted of $50.5 million in cash and the assumption of $0.8 million in liabilities. During the three months ended June 30, 2010, the Company finalized the purchase accounting for this acquisition. The preliminary purchase price was allocated to the acquired assets based on the estimated fair value of the acquired assets at the date of acquisition. Certain adjustments were made to the assets acquired upon a finalization of the appraisal of certain tangible and intangible assets during the six months ended June 30, 2010.

The following table summarizes the aggregate purchase consideration paid and the amounts of assets acquired at the acquisition date (in thousands), the adjustments to which are reflected in the Company's condensed consolidated balance sheet for the year ended December 31, 2009:


	Final Purchase Price Allocation		Preliminary Purchase Price Allocation
Current assets	$	6,165	$	—
Property and equipment		9,057		32,015
Intangible assets (1)		30,074		19,260

Fair value of net assets acquired	$	45,296	$	51,275

Goodwill (2)		5,979		—

(1)	Consists of customer relationships of approximately $22.9 million and network location of approximately $7.2 million, as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is expected to be deductible for income tax purposes. The goodwill was allocated to the rental and management segment.

Cincinnati Bell Acquisition—On December 23, 2009, the Company acquired 196 towers from Cincinnati Bell Inc. This acquisition had a final purchase price, after certain post-closing adjustments, of $99.9 million. During the three months ended June 30, 2010, the Company made adjustments to preliminary estimates to the purchase accounting for this acquisition. The preliminary purchase price was allocated to the acquired assets based on the estimated fair value of the acquired assets at the date of acquisition, subject to subsequent adjustments as the preliminary estimates of the fair value of the assets were updated.


	Final Purchase Price Allocation			Preliminary Purchase Price Allocation
Long-term assets	$	800		$	—
Property and equipment		21,950			16,147
Intangible assets (1)		74,500			83,723
Current liabilities		(5,200	)		—

Fair value of net assets acquired	$	92,050		$	99,870

Goodwill (2)		7,819			—

(1)	Consists of customer relationships of approximately $61.0 million and network location of approximately $13.5 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is expected to be deductible for income tax purposes. The goodwill was allocated to the rental and management segment.

U.S. Acquisitions—During the six months ended June 30, 2010, the Company acquired a total of 200 towers in the United States for $113.0 million. The acquisition of these towers is consistent with the Company's strategy to expand in selected geographic areas and have been accounted for as business combinations.

The following table summarizes the preliminary allocation of the aggregate purchase consideration paid and the amounts of assets acquired based on the estimated fair value of the acquired assets at the date of acquisition (in thousands):


Property and equipment	$	14,405
Intangible assets (1)		98,575

Fair value of net assets acquired	$	112,980

(1)	Consists of customer relationships of approximately $75.3 million and network location of approximately $23.3 million. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

The allocation of the purchase price will be finalized upon completion of analyses of the fair value of the assets acquired and may result in the recognition of goodwill.

Chile Acquisition—On June 29, 2010, the Company entered into definitive agreements to purchase up to 287 tower sites from Telefónica Chile S.A. and its affiliates. The Company purchased 113 of these tower sites on June 29, 2010 for an aggregate purchase price of $19.5 million, and expects to close on the remaining tower sites by the end of 2010, subject to customary closing conditions. The acquisition is consistent with the Company's strategy to expand in selected international markets.

This acquisition has been accounted for as a business combination. The purchase price has been preliminarily allocated to property and equipment and the allocation of the purchase price will be finalized upon completion of analyses of the fair value of the assets acquired.

ETIPL Acquisition—On February 24, 2010, the Company announced that its indirectly held, wholly owned Indian subsidiary, Transcend Infrastructure Limited, had entered into a definitive stock purchase agreement pursuant to which it will acquire from Essar Telecom Infrastructure Holding Overseas Ltd., Essar Securities Limited, and Essar Investments, Limited, each an Indian company, substantially all the issued and outstanding shares of Essar Telecom Infrastructure Private Limited ("ETIPL"), a company formed under the laws of India. ETIPL owns and operates approximately 4,450 towers in India, including a number of tower sites that are currently under construction. The total consideration for the acquisition is estimated to be approximately $430 million and is subject to certain post closing adjustments. The consideration to be provided will be satisfied with cash and the assumption of ETIPL's net liabilities at closing. The Company expects to use its Revolving Credit Facility, along with cash on hand, to satisfy the cash requirements at closing. Consummation of the acquisition is subject to customary closing conditions, as well as approval from India's Foreign Investment Promotion Board, which the Company received on July 26, 2010. The Company expects the transaction to close by the end of the third quarter of 2010.

Business Segments

6 Months Ended

Jun. 30, 2010

Business Segments

12.

Business Segments

The Company operates in two business segments: rental and management and network development services. The rental and management segment provides for the leasing and subleasing of antenna space on multi-tenant towers and other properties for a diverse range of customers primarily in the wireless communications and broadcast industries. Through its network development services segment, the Company offers tower-related services in the United States, including site acquisition, zoning and permitting services and structural analyses services which directly support the Company's site leasing business and the addition of new tenants and equipment on its sites.

The accounting policies applied in compiling segment information below are similar to those described in the Company's Annual Report on Form 10-K for the year ended December 31, 2009. In evaluating financial performance, management focuses on segment gross margin and segment operating profit. The Company defines segment gross margin as segment revenue less segment operating expenses excluding depreciation, amortization and accretion; selling, general, administrative and development expense; and other operating expenses. The Company defines segment operating profit as segment gross margin less selling, general, administrative and development expense attributable to the segment, excluding stock-based compensation expense and corporate expenses. For reporting purposes, the rental and management segment operating profit and segment gross margin also include interest income, TV Azteca, net. These measures of segment gross margin and segment operating profit are also before interest income, interest expense, loss on retirement of long-term obligations, other income (expense), net income attributable to noncontrolling interest, income (loss) on equity method investments, income taxes and discontinued operations.

The Company's reportable segments are strategic business units that offer different services. They are managed separately because each segment requires different resources, skill sets and marketing strategies. Summarized financial information concerning the Company's reportable segments for the three and six months ended June 30, 2010 and 2009 is shown in the tables below. The Other column below represents amounts excluded from specific segments, such as stock-based compensation expense and corporate expenses included in selling, general, administrative and development expense; other operating expense; interest income; interest expense; loss on retirement of long-term obligations; and other income (expense), as well as reconciles segment operating profit to income (loss) before income taxes, noncontrolling interest and income (loss) on equity method investments.


Three months ended June 30, 2010	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	456,481	$	13,456			$	469,937
Segment operating expenses		105,773		6,426				112,199
Interest income, TV Azteca, net		3,585						3,585

Segment gross margin		354,293		7,030				361,323

Segment selling, general, administrative and development expense		23,337		1,491				24,828

Segment operating profit	$	330,956	$	5,539				336,495

Other selling, general, administrative and development expense					$	28,754		28,754
Depreciation, amortization and accretion	$	107,904	$	658		1,841		110,403
Other expense (principally interest expense)						67,171		67,171

Income from continuing operations before income taxes and income on equity method investments							$	130,167

Three months ended June 30, 2009	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	406,751	$	16,607			$	423,358
Segment operating expenses		92,330		10,243				102,573
Interest income, TV Azteca, net		3,585						3,585

Segment gross margin		318,006		6,364				324,370

Segment selling, general, administrative and development expense		22,621		1,412				24,033

Segment operating profit	$	295,385	$	4,952			$	300,337

Other selling, general, administrative and development expense					$	25,828		25,828
Depreciation, amortization and accretion	$	99,944	$	692		1,827		102,463
Other expense (principally interest expense)						69,197		69,197

Income from continuing operations before income taxes and income on equity method investments							$	102,849


Six months ended June 30, 2010	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	900,299	$	24,072			$	924,371
Segment operating expenses		206,197		12,471				218,668
Interest income, TV Azteca, net		7,084		—				7,084

Segment gross margin		701,186		11,601				712,787

Segment selling, general, administrative and development expense		46,512		3,110				49,622

Segment operating profit	$	654,674	$	8,491				663,165

Other selling, general, administrative and development expense					$	57,487		57,487
Depreciation, amortization and accretion	$	216,113	$	1,339		3,786		221,238
Other expense (principally interest expense)						129,444		129,444

Income from continuing operations before income taxes and income on equity method investments							$	254,996

Six months ended June 30, 2009	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	802,698	$	29,338			$	832,036
Segment operating expenses		182,420		17,858				200,278
Interest income, TV Azteca, net		7,084		—				7,084

Segment gross margin		627,362		11,480				638,842

Segment selling, general, administrative and development expense		40,265		2,947				43,212

Segment operating profit	$	587,097	$	8,533			$	595,630

Other selling, general, administrative and development expense					$	64,281		64,281
Depreciation, amortization and accretion	$	197,326	$	1,357		3,648		202,331
Other expense (principally interest expense)						133,384		133,384

Income from continuing operations before income taxes and income on equity method investments							$	195,634

Subsequent Events

6 Months Ended

Jun. 30, 2010

Subsequent Events

13.

Subsequent Events

U.S. Acquisition—On July 22, 2010, the Company acquired 63 communication tower sites for an aggregate purchase price of $43.8 million.

Revolving Credit Facility—On July 23, 2010, the Company borrowed $350.0 million under the Revolving Credit Facility, which, in addition to cash on hand, will be used to finance the ETIPL acquisition.

Description of Business, Basis of Presentation and Accounting Policies (Policy)	6 Months Ended
	Jun. 30, 2010
Significant Accounting Policies and Use of Estimates	Significant Accounting Policies and Use of Estimates—The preparation of financial statements in conformity with accounting principles generally accepted in the United States ("GAAP") requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results may differ from those estimates, and such differences could be material to the accompanying condensed consolidated financial statements.
Concentration Of Credit Risk	Concentrations of Credit Risk—The Company is subject to concentrations of credit risk related to its cash and cash equivalents, notes receivable, trade receivables, deferred rent asset and derivative instruments. The Company mitigates its risk with respect to cash and cash equivalents and derivative instruments by maintaining its deposits and contracts at high quality financial institutions and monitoring the credit ratings of those institutions.
Foreign Currency Transactions and Translations	Foreign Currency—As a result of changes to the organizational structure of the Company's subsidiaries in Latin America in 2010, the Company has determined that effective January 1, 2010, the functional currency of its foreign subsidiary in Brazil is the Brazilian Real. From that point forward, all assets and liabilities held by the subsidiary in Brazil are translated into U.S. Dollars at the exchange rate in effect at the end of the applicable reporting period. Revenues and expenses are translated at the average monthly exchange rates and the cumulative translation effect is included in stockholders' equity. The change in functional currency from U.S. Dollars to Brazilian Real gave rise to an increase in the net value of certain non-monetary assets and liabilities. The aggregate impact on such assets and liabilities was $38.1 million with an offsetting increase in accumulated other comprehensive income (loss).
Recently Adopted Accounting Standards and Accounting Standards Updates	Recently Adopted Accounting Standards—In January 2010, the Financial Accounting Standards Board ("FASB") issued guidance clarifying existing disclosure requirements and adding disclosure requirements with respect to fair value measurements. This guidance was effective for the Company as of January 1, 2010 and had no impact on its consolidated results of operations or financial position. Accounting Standards Updates—In October 2009, the FASB issued new guidance which establishes accounting and reporting guidance for arrangements including multiple revenue-generating activities. This guidance requires companies to allocate the overall consideration to each deliverable under the arrangement using the estimated selling prices in the absence of vendor specific objective evidence or third-party evidence of selling price for deliverables. This guidance is effective for any contracts entered into, or materially modified by, the Company after January 1, 2011, with early adoption available. The Company is evaluating the impact, if any, that this update will have on its condensed consolidated results of operations and financial position.

Goodwill and Other Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2010

Schedule of goodwill


Balance as of December 31, 2009 as adjusted for purchase accounting measurement period of adjustments	$	2,255,234
Effect of foreign currency translation		709

Balance as of June 30, 2010	$	2,255,943

Company's other intangible assets


	Estimated Useful Lives	June 30, 2010			December 31, 2009 (3)
	(years)	(in thousands)
Acquired network location (1)	20	$	1,129,845		$	1,106,498
Acquired customer base	15-20		752,276			756,928
Acquired customer relationship	20		939,715			878,117
Acquired licenses and other intangibles	5-15		21,574			21,574
Economic Rights, TV Azteca	70		30,292			30,292

Total			2,873,702			2,793,409
Less accumulated amortization			(1,316,392	)		(1,238,579	)

Intangible assets, net			1,557,310			1,554,830
Deferred financing costs, net (2)	N/A		39,182			43,695

Other intangible assets, net		$	1,596,492		$	1,598,525

(1)	Acquired network location intangibles are amortized over the shorter of the term of the corresponding ground lease or 20 years, as the Company considers these intangibles to be directly related to the tower assets.

(2)	Deferred financing costs are amortized over the term of the respective debt instruments to which they relate. This amortization is included in interest expense, rather than in amortization expense.

(3)	December 31, 2009 balances have been revised to reflect purchase accounting adjustments.

Derivative Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2010

Schedule of interest rate swap agreements impact on other comprehensive income


As of June 30, 2010	Balance Sheet Location	Notional Amount		Carrying Amount and Fair Value
Liabilities:
Interest rate swap agreements	Other long-term liabilities	$	625,000	$	11,321

As of December 31, 2009	Balance Sheet Location	Notional Amount		Carrying Amount and Fair Value
Liabilities:
Interest rate swap agreements	Other long-term liabilities	$	625,000	$	18,852

Schedule of derivative financial instruments


Six Months Ended June 30, 2010
Amount of Gain/(Loss) Recognized in OCI on Derivatives (Effective Portion)	Location of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Amount of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Location of Gain/ (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Gain/(Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)
$(4,771)	Interest expense	$(9,373)	N/A	N/A

Six Months Ended June 30, 2009
Amount of Gain/(Loss) Recognized in OCI on Derivatives (Effective Portion)	Location of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Amount of Gain/ (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Location of Gain/ (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Gain/(Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)
$(9,678)	Interest expense	$(7,649)	N/A	N/A

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2010

Assets and liabilities measured at fair value on a recurring basis


	June 30, 2010
	Fair Value Measurements Using					Assets/Liabilities at Fair Value
	Level 1		Level 2		Level 3	Assets/Liabilities at Fair Value
	(in thousands)
Assets:
Short-term investments and available-for-sale securities (1)	$	27,891				$	27,891
Liabilities:
Interest rate swap agreements (2)			$	11,321		$	11,321

	December 31, 2009
	Fair Value Measurements Using					Assets/Liabilities at Fair Value
	Level 1		Level 2		Level 3	Assets/Liabilities at Fair Value
	(in thousands)
Assets:
Short-term investments and available-for-sale securities (1)	$	9,776				$	9,776
Liabilities:
Interest rate swap agreements (2)			$	18,852		$	18,852

(1)	Consists of available-for-sale securities traded on active markets as well as certain Brazilian Treasury securities that are highly liquid and actively traded in over-the-counter markets.

(2)	Consists of interest rate swap agreements based on the London Interbank Offering Rate ("LIBOR") whose value is determined using a pricing model with inputs that are observable in the market or can be derived principally from, or corroborated by, observable market data.

- Definition

This element represents the disclosure related to the fair value measurement of assets and liabilities which includes [financial] instruments measured at fair value that are classified in stockholders' equity. Such assets and liabilities may be measured on a recurring or nonrecurring basis. The disclosures which may be required or desired include: (1) for assets and liabilities measured on a recurring basis, disclosure may include: (a) the fair value measurements at the reporting date; (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3); (c) for fair value measurements using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (i) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (ii) purchases, sales, issuances, and settlements (net); (iii) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs); (d) the amount of the total gains or losses for the period in subparagraph (c) (i) above included in earnings (or changes in net assets) that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date and a description of where those unrealized gains or losses are reported in the statement of income (or activities); (e) the valuation technique(s) used to measure fair value and a discussion of changes in valuation techniques, if any, during the period and (2) for assets and liabilities that are measured at fair value on a nonrecurring basis (for example, impaired assets) disclosure may include, in addition to (a) above: (a) the reasons for the fair value measurements recorded; (b) the same as (b) above; (c) for fair value measurements using significant unobservable inputs (Level 3), a description of the inputs and the information used to develop the inputs; and (d) the valuation technique(s) used to measure fair value and a discussion of changes, if any, in the valuation technique(s) used to measure similar assets and/or liabilities in prior periods.

+ References+ Details

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2010

Summary of the Company's option activity


	Number of Options
Outstanding as of January 1, 2010	11,434,178
Granted	1,066,845
Exercised	(2,729,388	)
Forfeited	(129,459	)
Expired	(24,640	)

Outstanding as of June 30, 2010	9,617,536

Assumptions used to determine the grant date fair value for options granted


Range of risk-free interest rate		1.90% - 2.39%
Weighted average risk-free interest rate		2.38%
Expected life of option grants		4.6
Range of expected volatility of underlying stock price		37.11% - 37.30%
Weighted average expected volatility of underlying stock price		37.13%
Expected annual dividends		N/A

Summary of the Company's restricted stock unit activity


	Number of Units
Outstanding as of January 1, 2010	2,026,032
Granted	889,610
Vested	(552,564	)
Forfeited	(65,925	)

Outstanding as of June 30, 2010	2,297,153

Schedule Of Employee Stock Purchase Plan Valuation Assumptions


Approximate risk-free interest rate		0.22%
Expected life of shares		6 months
Expected volatility of underlying stock price		35.27%
Expected annual dividends		N/A

Earnings per Common Share (Tables)

6 Months Ended

Jun. 30, 2010

Schedule of earnings per share basic and diluted by common class


	Three Months Ended June 30,				Six Months Ended June 30,
	2010		2009		2010		2009
Income from continuing operations attributable to American Tower Corporation	$	99,671	$	51,229	$	195,954	$	106,760

Effect of convertible notes		—		747		—		1,494

Income available to common shareholders, as adjusted for diluted earnings	$	99,671	$	51,976	$	195,954	$	108,254

Basic weighted average common shares outstanding		402,733		397,418		402,540		397,300
Dilutive securities:
Stock options, warrants and convertible notes		2,291		11,414		3,145		11,555

Diluted weighted average common shares outstanding		405,024		408,832		405,685		408,855

Basic income from continuing operations attributable to American Tower Corporation per common share	$	0.25	$	0.13	$	0.49	$	0.27

Diluted income from continuing operations attributable to American Tower Corporation per common share	$	0.25	$	0.13	$	0.48	$	0.26

Acquisitions (Tables)

6 Months Ended

Jun. 30, 2010

U.S. Acquisition [Member]

Schedule of aggregate purchase consideration paid and the amount of assets acquired


Property and equipment	$	14,405
Intangible assets (1)		98,575

Fair value of net assets acquired	$	112,980

(1)	Consists of customer relationships of approximately $75.3 million and network location of approximately $23.3 million. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

XCEL Acquisition [Member]

Schedule of aggregate purchase consideration paid and the amount of assets acquired


	Final Purchase Price Allocation			Preliminary Purchase Price Allocation
Current and non-current assets	$	59,612		$	59,612
Property and equipment		83,523			83,523
Intangible assets (1)		38,091			38,091
Current and other long-term liabilities		(135,824	)		(135,824	)

Fair value of net assets acquired	$	45,402		$	45,402

Goodwill (2)		52,631			50,641

(1)	Consists of customer relationships of approximately $18.3 million and network location of approximately $19.8 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is not expected to be deductible for local income tax purposes. The goodwill was allocated to the rental and management segment.

Insight Acquisition [Member]

Schedule of aggregate purchase consideration paid and the amount of assets acquired

	Final Purchase Price Allocation			Preliminary Purchase Price Allocation
Current and non-current assets	$	3,513		$	3,552
Property and equipment		19,625			19,625
Intangible assets (1)		2,709			4,408
Current and other long-term liabilities		(8,116	)		(8,694	)

Fair value of net assets acquired	$	17,731		$	18,891

Goodwill (2)		1,617			22

(1)	Consists of customer relationships of approximately $0.9 million and network location of approximately $1.8 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is not expected to be deductible for local income tax purposes. The goodwill was allocated to the rental and management segment.

Brazil Acquisition [Member]

Schedule of aggregate purchase consideration paid and the amount of assets acquired

	Final Purchase Price Allocation		Preliminary Purchase Price Allocation
Current assets	$	6,165	$	—
Property and equipment		9,057		32,015
Intangible assets (1)		30,074		19,260

Fair value of net assets acquired	$	45,296	$	51,275

Goodwill (2)		5,979		—

(1)	Consists of customer relationships of approximately $22.9 million and network location of approximately $7.2 million, as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is expected to be deductible for income tax purposes. The goodwill was allocated to the rental and management segment.

Cincinnati Bell Acquisition [Member]

Schedule of aggregate purchase consideration paid and the amount of assets acquired


	Final Purchase Price Allocation			Preliminary Purchase Price Allocation
Long-term assets	$	800		$	—
Property and equipment		21,950			16,147
Intangible assets (1)		74,500			83,723
Current liabilities		(5,200	)		—

Fair value of net assets acquired	$	92,050		$	99,870

Goodwill (2)		7,819			—

(1)	Consists of customer relationships of approximately $61.0 million and network location of approximately $13.5 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

(2)	Goodwill is expected to be deductible for income tax purposes. The goodwill was allocated to the rental and management segment.

Business Segments (Tables)

6 Months Ended

Jun. 30, 2010

Company's reportable segments


Three months ended June 30, 2010	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	456,481	$	13,456			$	469,937
Segment operating expenses		105,773		6,426				112,199
Interest income, TV Azteca, net		3,585						3,585

Segment gross margin		354,293		7,030				361,323

Segment selling, general, administrative and development expense		23,337		1,491				24,828

Segment operating profit	$	330,956	$	5,539				336,495

Other selling, general, administrative and development expense					$	28,754		28,754
Depreciation, amortization and accretion	$	107,904	$	658		1,841		110,403
Other expense (principally interest expense)						67,171		67,171

Income from continuing operations before income taxes and income on equity method investments							$	130,167

Three months ended June 30, 2009	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	406,751	$	16,607			$	423,358
Segment operating expenses		92,330		10,243				102,573
Interest income, TV Azteca, net		3,585						3,585

Segment gross margin		318,006		6,364				324,370

Segment selling, general, administrative and development expense		22,621		1,412				24,033

Segment operating profit	$	295,385	$	4,952			$	300,337

Other selling, general, administrative and development expense					$	25,828		25,828
Depreciation, amortization and accretion	$	99,944	$	692		1,827		102,463
Other expense (principally interest expense)						69,197		69,197

Income from continuing operations before income taxes and income on equity method investments							$	102,849


Six months ended June 30, 2010	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	900,299	$	24,072			$	924,371
Segment operating expenses		206,197		12,471				218,668
Interest income, TV Azteca, net		7,084		—				7,084

Segment gross margin		701,186		11,601				712,787

Segment selling, general, administrative and development expense		46,512		3,110				49,622

Segment operating profit	$	654,674	$	8,491				663,165

Other selling, general, administrative and development expense					$	57,487		57,487
Depreciation, amortization and accretion	$	216,113	$	1,339		3,786		221,238
Other expense (principally interest expense)						129,444		129,444

Income from continuing operations before income taxes and income on equity method investments							$	254,996

Six months ended June 30, 2009	Rental and Management		Network Development Services		Other		Total
	(in thousands)
Segment revenues	$	802,698	$	29,338			$	832,036
Segment operating expenses		182,420		17,858				200,278
Interest income, TV Azteca, net		7,084		—				7,084

Segment gross margin		627,362		11,480				638,842

Segment selling, general, administrative and development expense		40,265		2,947				43,212

Segment operating profit	$	587,097	$	8,533			$	595,630

Other selling, general, administrative and development expense					$	64,281		64,281
Depreciation, amortization and accretion	$	197,326	$	1,357		3,648		202,331
Other expense (principally interest expense)						133,384		133,384

Income from continuing operations before income taxes and income on equity method investments							$	195,634

Description of Business, Basis of Presentation and Accounting Policies (Details) (USD $)	6 Months Ended
	Jun. 30, 2010	Dec. 31, 2009
Number of customers in concentration	4
Accounts receivable, net	$ 48,872,000	$ 67,949,000
Notes receivable and other long-term assets	678,120,000	651,894,000
Impact of change in functional currency in AOCI	38,100,000
Grupo Iusacell [Member]
Accounts receivable, net	18,300,000
Impact of change in functional currency in AOCI	37,600,000
Largest United States Customers [Member]
Percentage revenue derived from concentration	60.00%
Notes receivable and other long-term assets	286,400,000
Accounts receivable, net, noncurrent	16,700,000
Largest Foreign Customer [Member]
Accounts receivable, net	16,700,000
Notes receivable and other long-term assets	$ 45,200,000
Largest Foreign Customer [Member] \| Grupo Iusacell [Member]
Percentage revenue derived from concentration	4.00%

Short-Term Investments and Available-For-Sale Securities (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2010
Brazilian Treasury securities	$ 27.7
Available-for-sale securities	$ 0.2

- Definition

For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading. Such securities are reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis.

+ References+ Details

Goodwill and Other Intangible Assets (Details) (USD $)

3 Months Ended

6 Months Ended

Jun. 30, 2010

Jun. 30, 2009

Jun. 30, 2010

Jun. 30, 2009

Dec. 31, 2009

Goodwill, Beginning Balance

$ 2,255,234,000

Effect of foreign currency translation

709,000

Goodwill, Ending Balance

2,255,943,000

Other intangible assets

2,873,702,000

2,793,409,000

^[1]

Less accumulated amortization

(1,316,392,000)

(1,238,579,000)

^[1]

Intangible assets, net

1,557,310,000

1,554,830,000

^[1]

Deferred financing costs, net

39,182,000

^[2]

39,182,000

^[2]

43,695,000

^[1],[2]

Other intangible assets, net

1,596,492,000

1,598,525,000

^[1]

Weighted average amortization period

Amortization of intangible assets

37,600,000

35,900,000

75,400,000

68,000,000

Acquired Network Location [Member]

Other intangible assets

1,129,845,000

^[3]

1,129,845,000

^[3]

1,106,498,000

^[1],[3]

Estimated Useful Lives (in years)

^[3]

Acquired Customer Lists [Member]

Other intangible assets

752,276,000

756,928,000

^[1]

Estimated Useful Lives, minimum (in years)

Estimated Useful Lives, maximum (in years)

Acquired Customer Relationships [Member]

Other intangible assets

939,715,000

878,117,000

^[1]

Estimated Useful Lives (in years)

Acquired Licenses And Other Intangibles [Member]

Other intangible assets

21,574,000

^[1]

Estimated Useful Lives, minimum (in years)

Estimated Useful Lives, maximum (in years)

Economic Rights, TV Azteca [Member]

Other intangible assets

$ 30,292,000

^[1]

Estimated Useful Lives (in years)

[1]	December 31, 2009 balances have been revised to reflect purchase accounting adjustments.
[2]	Deferred financing costs are amortized over the term of the respective debt instruments to which they relate. This amortization is included in interest expense, rather than in amortization expense.
[3]	Acquired network location intangibles are amortized over the shorter of the term of the corresponding ground lease or 20 years, as the Company considers these intangibles to be directly related to the tower assets.

Financing Transactions (Details)	6 Months Ended					1 Months Ended	6 Months Ended
Financing Transactions (Details)	Jun. 30, 2010 USD ($)	Jun. 30, 2009 USD ($)	Jun. 30, 2010 Revolving Credit Facility and Term Loan [Member] USD ($)	Jun. 30, 2010 XCEL Credit Facility [Member] USD ($)	Jun. 30, 2010 XCEL Credit Facility [Member] INR	Jul. 23, 2010 Stock Repurchase Program [Member] USD ($)	Jun. 30, 2010 Stock Repurchase Program [Member] USD ($)	Jun. 30, 2010 Common Class A [Member] Stock Repurchase Program [Member] USD ($)
Revolving credit facility, outstanding			$ 625,000,000	$ 77,300,000	3,400,000,000
Revolving credit facility, capacity			1,250,000,000		4,800,000,000
Undrawn letters of credit outstanding			3,100,000
Line of credit facility increase in borrowings capacity			325,000,000
Stock repurchase program							1,500,000,000
Class A common stock shares repurchased						26,100,000	879,700	4,600,000
Treasury stock activity	$ 196,343,000	$ 69,631,000				$ 984,400,000	$ 40,000,000	$ 196,300,000

Derivative Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended			6 Months Ended
	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2010 Interest Rate Contract [Member]	Jun. 30, 2010 Interest Rate Contract [Member] Interest Expense [Member]	Jun. 30, 2009 Interest Rate Contract [Member] Interest Expense [Member]	Jun. 30, 2010 Interest Rate Contract [Member] Other long-term liabilities [Member]	Dec. 31, 2009 Interest Rate Contract [Member] Other long-term liabilities [Member]
Number of interest rate swap agreements	13
Notional amount of cash flow hedges	$ 625,000					$ 625,000	$ 625,000
Derivative, lower variable interest rate range			2.86%
Derivative, higher variable interest rate range			4.08%
Carrying amount and fair value of interest rate swap agreements						11,321	18,852
Derivative instruments, gain (loss) recognized in other comprehensive income, effective portion, net, total	(4,771)	(9,678)
Amount of Gain/(Loss) Reclassified from accumulated OCI into Income (Effective Portion)				$ (9,373)	$ (7,649)

Fair Value Measurements (Details) (USD $)

Jun. 30, 2010

Dec. 31, 2009

Short-term investments and available-for-sale securities

$ 27,891,000

^[1]

$ 9,776,000

^[1]

Interest rate swap agreements

11,321,000

^[2]

18,852,000

^[2]

Fair Value, Inputs, Level 1 [Member]

Short-term investments and available-for-sale securities

27,891,000

^[1]

9,776,000

^[1]

Fair Value, Inputs, Level 2 [Member]

Interest rate swap agreements

11,321,000

^[2]

18,852,000

^[2]

Carrying Value, Fair Value Disclosure [Member]

Carrying value and fair value of long-term obligations, including current portion

4,200,000,000

Estimate of Fair Value, Fair Value Disclosure [Member]

Carrying value and fair value of long-term obligations, including current portion

$ 4,300,000,000

[1]	Consists of available-for-sale securities traded on active markets as well as certain Brazilian Treasury securities that are highly liquid and actively traded in over-the-counter markets.
[2]	Consists of interest rate swap agreements based on the London Interbank Offering Rate ("LIBOR") whose value is determined using a pricing model with inputs that are observable in the market or can be derived principally from, or corroborated by, observable market data.

Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended
Income Taxes (Details) (USD $)	Jun. 30, 2010	Mar. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Unrecognized Tax Benefits, Beginning Balance		$ 87,975,000	$ 87,975,000
Tax benefits impacting discontinued operations	35,700,000		35,700,000
Total tax benefits affecting effective tax rate	32,600,000		32,600,000
Deferred tax assets	8,000,000		8,000,000
Unrecognized Tax Benefits Increase In Tax Positions, Minimum	0		0
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change	2,000,000		2,000,000
Unrecognized Tax Benefits, Ending Balance	76,319,000		76,319,000
Additions based on tax positions related to the current year			10,158,000
Additions for tax positions of prior year			8,948,000
Reductions for tax positions of prior years			(30,855,000)
Foreign currency			146,000
Reduction as a result of the lapse of statute limitations			(53,000)
Penalties and tax-related interest expense	700,000		1,400,000
Accrued income tax-related interest and penalties	16,800,000		16,800,000	15,200,000
Reversal of accrued income tax liabilities		32,600,000
Additional analysis of net operating losses			26,300,000
Additional Income Tax Reserves			$ 19,100,000

Stock-Based Compensation (Details) (USD $)	3 Months Ended		6 Months Ended
Stock-Based Compensation (Details) (USD $)	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2010	Jun. 30, 2009
Stock-based compensation expense	$ 13,228,000	$ 12,836,000	$ 26,792,000	$ 37,174,000
Stock based compensation expenses related to modification of the vesting and exercise terms for a certain employee's equity awards				6,600,000
Stock Option [Member]
Minimum Range of risk-free interest rate			1.90%
Maximum Range of risk-free interest rate			2.39%
Approximate risk-free interest rate			2.38%
Expected life of options granted			4.6
Minimum Range of expected volatility of underlying stock price			37.11%
Maximum Range of expected volatility of underlying stock price			37.30%
Expected volatility of underlying stock price			37.13%
Weighted average grant date fair value per share			$ 14.97
Total unrecognized compensation expense related to unvested stock options	40,800,000		40,800,000
Expected recognition of stock option compensation expense weighted average period (in years)			2
Outstanding as of January 1, 2010			11,434,178
Granted			1,066,845
Exercised			(2,729,388)
Forfeited			(129,459)
Expired			(24,640)
Outstanding as of June 30, 2010	9,617,536		9,617,536
Restricted Stock [Member]
Stock granted for purchase of Common Stock pursuant to its 2007 Equity Incentive Plan ("2007 Plan").			900,000
Outstanding as of January 1, 2010			2,026,032
Granted			889,610
Vested			(552,564)
Forfeited			(65,925)
Outstanding as of June 30, 2010	2,297,153		2,297,153
Total unrecognized compensation expense related to unvested restricted stock units granted under the 2007 Plan	70,800,000		70,800,000
Expected recognition of restricted stock units granted compensation expense weighted average period (in years)			3
Employee Stock Purchase Plan [Member]
Approximate risk-free interest rate			0.22%
Expected life of options granted			0.5
Expected volatility of underlying stock price			35.27%
Employee Stock Purchase Plan			38,542
Purchased Shares Fair Value Price Per Share ESPP			$ 9.51

Earnings per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2010	Jun. 30, 2009
Income from continuing operations attributable to American Tower Corporation	$ 99,671	$ 51,229	$ 195,954	$ 106,760
Dilutive Securities		747		1,494
Income available to common shareholders, as adjusted for diluted earnings	$ 99,671	$ 51,976	$ 195,954	$ 108,254
Basic weighted average common shares outstanding	402,733,000	397,418,000	402,540,000	397,300,000
Stock options, warrants and convertible notes	2,291,000	11,414,000	3,145,000	11,555,000
Diluted weighted average common shares outstanding	405,024,000	408,832,000	405,685,000	408,855,000
Basic income from continuing operations attributable to American Tower Corporation per common share	$ 0.25	$ 0.13	$ 0.49	$ 0.27
Diluted income from continuing operations attributable to American Tower Corporation per common share	$ 0.25	$ 0.13	$ 0.48	$ 0.26
Stock Options [Member]
Shares issuable upon conversion of the convertible notes	3,400,000	10,300,000	1,900,000	10,400,000
Convertible Debt Securities [Member]
Shares issuable upon conversion of the convertible notes	300,000	1,200,000	300,000	1,200,000

Commitments and Contingencies (Details) (USD $)	6 Months Ended
Commitments and Contingencies (Details) (USD $)	Jun. 30, 2010
ATT Transaction [Member]
Number Of Towers Leased Or Subleased	2,500
Average lease term (in years)	27
Aggregate Purchase Option Price For Towers	$ 432,800,000
Accretion Rate On Lease (per year)	10.00%
ALLTEL Transaction [Member]
Aggregate Purchase Option Price For Towers	64,200,000
Accretion Rate On Lease (per year)	3.00%
Sublease Term Towers	15
Number Of Tower Rights	1,800
Purchase Price Per Tower	27,500
Purchase Price Of Tower In Shares Of Common Stock	769
XCEL Litigation [Member]
Holdback escrow account	7,500,000
Escrow account	15,700,000
Additional release from holdback escrow account	2,800,000
Additional release from escrow account	12,000,000
Potential punitive damages	69,000,000
Mexico Litigation [Member]
Potential punitive damages	$ 23,000,000

Acquisitions (Details) (USD $)

6 Months Ended

Jun. 30, 2010

Jul. 31, 2010

XCEL Acquisition [Member]

Acquired 100% of Business

100.00%

Aggregate purchase price

$ 98,000,000

Insight Acquisition [Member]

Acquired 100% of Business

100.00%

Preliminary post closing price adjustments

19,300,000

Brazil Acquisition [Member]

Aggregate purchase price

51,300,000

Cash portion of purchase price of towers in Brazil

50,500,000

Current and other long-term liabilities

(800,000)

Number Of Towers Acquired

230

Cincinnati Bell Acquisition [Member]

Aggregate purchase price

99,900,000

Number Of Towers Acquired

196

U.S. Acquisition [Member]

Aggregate purchase price

113,000,000

43,800,000

Property and equipment

14,405,000

Intangible assets

98,575,000

^[1]

Fair value of net assets acquired

112,980,000

Number Of Towers Acquired

200

Chile Acquisition [Member]

Aggregate purchase price

19,500,000

Number Of Additional Towers Obligated

287

Number Of Towers Acquired

113

ETIPL Acquisition [Member]

Number Of Towers Owned And Operated

4,450

Estimated Aggregate purchase price

430,000,000

Preliminary Purchase Price Allocation [Member] | XCEL Acquisition [Member]

Current and non-current assets

59,612,000

Property and equipment

83,523,000

Intangible assets

38,091,000

^[2]

Current and other long-term liabilities

(135,824,000)

Fair value of net assets acquired

45,402,000

Goodwill

50,641,000

^[3]

Preliminary Purchase Price Allocation [Member] | Insight Acquisition [Member]

Current and non-current assets

3,552,000

Property and equipment

19,625,000

Intangible assets

4,408,000

^[4]

Current and other long-term liabilities

(8,694,000)

Fair value of net assets acquired

18,891,000

Goodwill

22,000

^[3]

Preliminary Purchase Price Allocation [Member] | Brazil Acquisition [Member]

Property and equipment

32,015,000

Intangible assets

19,260,000

^[5]

Fair value of net assets acquired

51,275,000

Preliminary Purchase Price Allocation [Member] | Cincinnati Bell Acquisition [Member]

Property and equipment

16,147,000

Intangible assets

83,723,000

^[6]

Fair value of net assets acquired

99,870,000

Final Purchase Price Allocation [Member] | XCEL Acquisition [Member]

Current and non-current assets

59,612,000

Property and equipment

83,523,000

Intangible assets

38,091,000

^[2]

Current and other long-term liabilities

(135,824,000)

Fair value of net assets acquired

45,402,000

Goodwill

52,631,000

^[3]

Final Purchase Price Allocation [Member] | Insight Acquisition [Member]

Current and non-current assets

3,513,000

Property and equipment

19,625,000

Intangible assets

2,709,000

^[4]

Current and other long-term liabilities

(8,116,000)

Fair value of net assets acquired

17,731,000

Goodwill

1,617,000

^[3]

Final Purchase Price Allocation [Member] | Brazil Acquisition [Member]

Current assets

6,165,000

Property and equipment

9,057,000

Intangible assets

30,074,000

^[5]

Fair value of net assets acquired

45,296,000

Goodwill

5,979,000

^[3]

Final Purchase Price Allocation [Member] | Cincinnati Bell Acquisition [Member]

Long-term assets

800,000

Property and equipment

21,950,000

Intangible assets

74,500,000

^[6]

Current Liabilities

(5,200,000)

Fair value of net assets acquired

92,050,000

Goodwill

$ 7,819,000

^[3]

[1]	Consists of customer relationships of approximately $75.3 million and network location of approximately $23.3 million. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.
[2]	Consists of customer relationships of approximately $18.3 million and network location of approximately $19.8 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.
[3]	Goodwill is not expected to be deductible for local income tax purposes. The goodwill was allocated to the rental and management segment.
[4]	Consists of customer relationships of approximately $0.9 million and network location of approximately $1.8 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.
[5]	Consists of customer relationships of approximately $22.9 million and network location of approximately $7.2 million, as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.
[6]	Consists of customer relationships of approximately $61.0 million and network location of approximately $13.5 million as of June 30, 2010. The customer relationships and network location are being amortized on a straight-line basis over a period of 20 years.

Acquisitions Parenthetical (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2010
XCEL Acquisition [Member]
Customer relationships	$ 18.3
Network capacity	19.8
Useful life of intangible assets	20
Insight Acquisition [Member]
Customer relationships	0.9
Network capacity	1.8
Useful life of intangible assets	20
Brazil Acquisition [Member]
Customer relationships	22.9
Network capacity	7.2
Useful life of intangible assets	20
U.S. Acquisition [Member]
Customer relationships	75.3
Network capacity	23.3
Useful life of intangible assets	20
Cincinnati Bell Acquisition [Member]
Customer relationships	61.0
Network capacity	$ 13.5
Useful life of intangible assets	20

Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2010	Jun. 30, 2009
Segment revenues	$ 469,937	$ 423,358	$ 924,371	$ 832,036
Segment operating expenses	112,199	102,573	218,668	200,278
Interest income, TV Azteca, net	3,585	3,585	7,084	7,084
Segment gross margin	361,323	324,370	712,787	638,842
Segment selling, general, administrative and development expense	24,828	24,033	49,622	43,212
Segment operating profit	336,495	300,337	663,165	595,630
Other selling, general, administrative and development expense	28,754	25,828	57,487	64,281
Depreciation, amortization and accretion	110,403	102,463	221,238	202,331
Other expense (principally interest expense)	67,171	69,197	129,444	133,384
Income from continuing operations before income taxes and income on equity method investments	130,167	102,849	254,996	195,634
Rental And Management [Member]
Segment revenues	456,481	406,751	900,299	802,698
Segment operating expenses	105,773	92,330	206,197	182,420
Interest income, TV Azteca, net	3,585	3,585	7,084	7,084
Segment gross margin	354,293	318,006	701,186	627,362
Segment selling, general, administrative and development expense	23,337	22,621	46,512	40,265
Segment operating profit	330,956	295,385	654,674	587,097
Depreciation, amortization and accretion	107,904	99,944	216,113	197,326
Network Development Services [Member]
Segment revenues	13,456	16,607	24,072	29,338
Segment operating expenses	6,426	10,243	12,471	17,858
Segment gross margin	7,030	6,364	11,601	11,480
Segment selling, general, administrative and development expense	1,491	1,412	3,110	2,947
Segment operating profit	5,539	4,952	8,491	8,533
Depreciation, amortization and accretion	658	692	1,339	1,357
Other Segment [Member]
Other selling, general, administrative and development expense	28,754	25,828	57,487	64,281
Depreciation, amortization and accretion	1,841	1,827	3,786	3,648
Other expense (principally interest expense)	$ 67,171	$ 69,197	$ 129,444	$ 133,384

Subsequent Events [Details] (USD $) In Millions, unless otherwise specified						7 Months Ended
	Jul. 31, 2010 U.S. Acquisition [Member]	Jun. 30, 2010 U.S. Acquisition [Member]	Jun. 30, 2010 XCEL Acquisition [Member]	Jun. 30, 2010 Brazil Acquisition [Member]	Jun. 30, 2010 Cincinnati Bell Acquisition [Member]	Jul. 31, 2010 Revolving Credit Facility and Term Loan [Member]
Wireless communications sites acquired	63
Business Acquisition, Cost of Acquired Entity, Purchase Price	$ 43.8	$ 113.0	$ 98.0	$ 51.3	$ 99.9
Line of Credit Facility, Increase, Additional Borrowings						$ 350.0
Number Of Towers Acquired		200		230	196