American Tower (AMT) 10-Q 30 Jul 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Jun. 30, 2014	Jul. 21, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
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	'	396,144,247

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS-Unaudited (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
CURRENT ASSETS:	'	'
Cash and cash equivalents	$282,959	$293,576
Restricted cash	158,992	152,916
Short-term investments	15,298	18,612	[1]
Accounts receivable, net	174,612	151,084
Prepaid and other current assets	342,798	340,885	[2]
Deferred income taxes	23,786	22,401
Total current assets	998,445	979,474
PROPERTY AND EQUIPMENT, net	7,589,815	7,189,465
GOODWILL	3,854,931	3,808,426	[3]
OTHER INTANGIBLE ASSETS, net	6,637,882	6,580,305	[3]
DEFERRED INCOME TAXES	268,349	264,294
DEFERRED RENT ASSET	983,140	918,847
NOTES RECEIVABLE AND OTHER NON-CURRENT ASSETS	515,175	504,466
TOTAL	20,847,737	20,245,277
CURRENT LIABILITIES:	'	'
Accounts payable	132,734	172,426
Accrued expenses	422,614	415,075	[2]
Distributions payable	139,837	575
Accrued interest	117,632	105,751
Current portion of long-term obligations	1,225,992	70,132
Unearned revenue	204,437	162,079
Total current liabilities	2,243,246	926,038
LONG-TERM OBLIGATIONS	12,749,471	14,408,146
ASSET RETIREMENT OBLIGATIONS	556,881	526,930
OTHER NON-CURRENT LIABILITIES	889,975	794,123
Total liabilities	16,439,573	16,655,237
COMMITMENTS AND CONTINGENCIES	'	'
EQUITY:	'	'
Preferred stock: $.01 par value; 20,000,000 shares authorized; 5.25% Mandatory Convertible Preferred Stock, Series A, 6,000,000 and no shares issued and outstanding, respectively	60	0
Common stock: $.01 par value; 1,000,000,000 shares authorized; 398,811,474 and 397,674,350 shares issued; and 396,001,448 and 394,864,324 shares outstanding, respectively	3,988	3,976
Additional paid-in capital	5,772,269	5,130,616
Distributions in excess of earnings	-911,163	-1,081,467
Accumulated other comprehensive loss	-250,920	-311,220
Treasury stock (2,810,026 shares at cost)	-207,740	-207,740
Total American Tower Corporation equity	4,406,494	3,534,165
Noncontrolling interest	1,670	55,875
Total equity	4,408,164	3,590,040
TOTAL	$20,847,737	$20,245,277
[1]	Consists of highly liquid investments with original maturities in excess of three months.
[2]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
[3]	Balances have been revised to reflect purchase accounting measurement period adjustments.

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS-Unaudited (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]	'	'
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, shares issued	6,000,000	0
Preferred stock, shares outstanding	6,000,000	0
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	398,811,474	397,674,350
Common Stock, Shares, Outstanding	396,001,448	394,864,324
Treasury stock, shares	2,810,026	2,810,026

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS-Unaudited (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
REVENUES:	'	'	'	'
Rental and management	$1,005,761	$789,199	$1,965,881	$1,566,632
Network development services	25,696	19,631	49,665	44,926
Total operating revenues	1,031,457	808,830	2,015,546	1,611,558
OPERATING EXPENSES:	'	'	'	'
Rental and management (including stock-based compensation expense of $343, $257, $715 and $503, respectively)	263,184	198,217	514,019	389,512
Network development services (including stock-based compensation expense of $110, $149, $242 and $341, respectively)	9,091	7,492	19,025	17,963
Depreciation, amortization and accretion	245,427	184,608	491,190	370,412
Selling, general, administrative and development expense (including stock-based compensation expense of $18,382, $16,649, $42,482 and $37,253, respectively)	98,499	99,803	208,528	200,956
Other operating expenses	12,757	5,898	26,648	20,217
Total operating expenses	628,958	496,018	1,259,410	999,060
OPERATING INCOME	402,499	312,812	756,136	612,498
OTHER INCOME (EXPENSE):	'	'	'	'
Interest income, TV Azteca, net of interest expense of $370, $371, $741 and $742 respectively	2,662	3,586	5,257	7,129
Interest income	2,281	1,412	4,299	3,126
Interest expense	-146,234	-100,815	-289,541	-212,581
Loss on retirement of long-term obligations	-1,284	-2,669	-1,522	-37,967
Other expense (including unrealized foreign currency losses of $23,553, $142,909, $25,558 and $120,766, respectively)	-16,463	-141,660	-20,206	-119,369
Total other expense	-159,038	-240,146	-301,713	-359,662
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	243,461	72,666	454,423	252,836
Income tax (provision) benefit	-21,802	11,447	-39,451	-7,775
NET INCOME	221,659	84,113	414,972	245,061
Net loss attributable to noncontrolling interest	12,772	15,708	21,958	26,167
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION STOCKHOLDERS	234,431	99,821	436,930	271,228
Dividends declared on preferred stock	-4,375	0	-4,375	0
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION COMMON STOCKHOLDERS	$230,056	$99,821	$432,555	$271,228
NET INCOME PER COMMON SHARE AMOUNTS:	'	'	'	'
Basic net income attributable to American Tower Corporation common stockholders (in dollars per share)	$0.58	$0.25	$1.09	$0.69
Diluted net income attributable to American Tower Corporation common stockholders (in dollars per share)	$0.58	$0.25	$1.08	$0.68
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:	'	'	'	'
Basic (in shares)	395,872	395,420	395,511	395,330
Diluted (in shares)	399,588	399,458	399,452	399,659
DISTRIBUTIONS DECLARED, PER SHARE (in dollars per share)	$0.34	$0.27	$0.66	$0.53

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS-Unaudited (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Stock-based compensation expense	$18,835	$17,055	$43,439	$38,097
Unrealized foreign currency losses	-23,553	-142,909	-25,558	-120,766
Rental And Management [Member]	'	'	'	'
Stock-based compensation expense	343	257	715	503
Network Development Services [Member]	'	'	'	'
Stock-based compensation expense	110	149	242	341
Selling General Administrative And Development Expense [Member]	'	'	'	'
Stock-based compensation expense	18,382	16,649	42,482	37,253
TV Azteca [Member]	'	'	'	'
Net of interest expense	$370	$371	$741	$742

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS)-Unaudited (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net income	$221,659	$84,113	$414,972	$245,061
Other comprehensive income (loss):	'	'	'	'
Changes in fair value of cash flow hedges, net of tax expense of ($141), $345, ($24) and $456, respectively	367	3,793	-337	2,749
Reclassification of unrealized losses on cash flow hedges to net income, net of taxes of $41, $59, $96 and $118, respectively	629	645	1,543	1,194
Foreign currency translation adjustments, net of taxes of ($692), ($7,149), $364 and $6,583, respectively	-3,104	-123,369	19,388	-95,942
Other comprehensive (loss) income	-2,108	-118,931	20,594	-91,999
Comprehensive income (loss)	219,551	-34,818	435,566	153,062
Comprehensive loss attributable to noncontrolling interest	36,370	18,426	61,664	27,257
Comprehensive income (loss) attributable to American Tower Corporation stockholders	$255,921	($16,392)	$497,230	$180,319

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)-Unaudited (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net change in fair value of cash flow hedges, tax	($141)	$345	($24)	$456
Reclassification of unrealized losses on cash flow hedges to net income, tax	41	59	96	118
Foreign currency translation adjustments, tax	($692)	($7,149)	$364	$6,583

CONDENSED_CONSOLIDATED_STATEME4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS-Unaudited (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
CASH FLOWS PROVIDED BY OPERATING ACTIVITIES:	'	'
Net income	$414,972	$245,061
Adjustments to reconcile net income to cash provided by operating activities:	'	'
Stock-based compensation expense	43,439	38,097
Depreciation, amortization and accretion	491,190	370,412
Loss on early retirement of securitized debt	1,269	35,288
Other non-cash items reflected in statements of operations	48,636	127,946
Increase in net deferred rent asset	-46,293	-53,017
Increase in restricted cash	-194	-27,961
Increase in assets	-28,473	-10,229
Increase in liabilities	147,836	58,924
Cash provided by operating activities	1,072,382	784,521
CASH FLOWS FROM INVESTING ACTIVITIES:	'	'
Payments for purchase of property and equipment and construction activities	-466,247	-280,605
Payments for acquisitions, net of cash acquired	-315,527	-311,170
Proceeds from sale of short-term investments and other non-current assets	338,787	27,978
Payments for short-term investments	-332,684	-36,881
Deposits, restricted cash, investments and other	-61,134	-1,096
Cash used for investing activities	-836,805	-601,774
CASH FLOWS FROM FINANCING ACTIVITIES:	'	'
Borrowings under credit facilities	360,000	249,000
Proceeds from issuance of senior notes, net	769,640	983,354
Proceeds from other long-term borrowings	3,033	16,000
Proceeds from issuance of Securities in securitization transaction, net	0	1,778,496
Repayments of notes payable, credit facilities and capital leases	-1,838,728	-2,938,699
(Distributions to) contributions from noncontrolling interest holders, net	-291	17,721
Purchases of common stock	0	-74,625
Proceeds from stock options and stock purchase plan	30,738	19,752
Proceeds from the issuance of preferred stock, net	583,326	0
Payment for early retirement of securitized debt	-6,767	-29,234
Deferred financing costs and other financing activities	-22,914	-13,641
Distributions paid on common stock	-127,269	-102,984
Cash used for financing activities	-249,232	-94,860
Net effect of changes in foreign currency exchange rates on cash and cash equivalents	3,038	-8,058
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	-10,617	79,829
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	293,576	368,618
CASH AND CASH EQUIVALENTS, END OF PERIOD	282,959	448,447
CASH PAID FOR INCOME TAXES (NET OF REFUNDS OF $6,187 AND $13,477, RESPECTIVELY)	35,776	17,153
CASH PAID FOR INTEREST	270,257	181,315
NON-CASH INVESTING AND FINANCING ACTIVITIES:	'	'
INCREASE IN ACCOUNTS PAYABLE AND ACCRUED EXPENSES FOR PURCHASES OF PROPERTY AND EQUIPMENT AND CONSTRUCTION ACTIVITIES	14,959	17,142
PURCHASES OF PROPERTY AND EQUIPMENT UNDER CAPITAL LEASES	14,585	9,422
SETTLEMENT OF ACCOUNTS RECEIVABLE DUE TO ACQUISITION	31,279	0
CONVERSION OF THIRD-PARTY DEBT TO EQUITY	$7,750	$0

CONDENSED_CONSOLIDATED_STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS-Unaudited (Parenthetical) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Statement of Cash Flows [Abstract]	'	'
Proceeds from income tax refunds	$6,187	$13,477

CONDENSED_CONSOLIDATED_STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY-Unaudited (USD $)	Total	Preferred Stock	Common Stock	Treasury Stock	Additional Paid-in Capital	Other Comprehensive (Loss) Income	Earnings (Distributions) in Excess of Distributions (Earnings)	Noncontrolling Interest
BALANCE at Dec. 31, 2012	$3,684,181,000	'	$3,959,000	($62,728,000)	$5,012,124,000	($183,347,000)	($1,196,907,000)	$111,080,000
BALANCE (shares) at Dec. 31, 2012	'	'	395,963,218	-872,005	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'
Stock-based compensation related activity (shares)	'	'	952,304	'	'	'	'	'
Stock-based compensation related activity	47,373,000	'	10,000	'	47,363,000	'	'	'
Issuance of common stock- stock purchase plan Shares	'	'	38,249	'	'	'	'	'
Issuance of common stock- stock purchase plan	2,327,000	'	0	'	2,327,000	'	'	'
Treasury stock activity (shares)	'	'	'	-951,884	'	'	'	'
Treasury stock activity	-74,625,000	'	'	-74,625,000	'	'	'	'
Changes in fair value of cash flow hedges, net of tax	2,749,000	'	'	'	'	2,456,000	'	293,000
Reclassification of unrealized losses on cash flow hedges to net income, net of tax	1,194,000	'	'	'	'	1,120,000	'	74,000
Foreign currency translation adjustment, net of tax	-95,942,000	'	'	'	'	-94,485,000	'	-1,457,000
Contributions from noncontrolling interest	18,020,000	'	'	'	'	'	'	18,020,000
Distributions to noncontrolling interest	-299,000	'	'	'	'	'	'	-299,000
Common stock dividends/distributions declared	-210,172,000	'	'	'	'	'	-210,172,000	'
Dividends declared on preferred stock	0	'	'	'	'	'	'	'
Net income (loss)	245,061,000	'	'	'	'	'	271,228,000	-26,167,000
BALANCE at Jun. 30, 2013	3,619,867,000	'	3,969,000	-137,353,000	5,061,814,000	-274,256,000	-1,135,851,000	101,544,000
BALANCE (shares) at Jun. 30, 2013	'	'	396,953,771	-1,823,889	'	'	'	'
BALANCE at Dec. 31, 2013	3,590,040,000	'	3,976,000	-207,740,000	5,130,616,000	-311,220,000	-1,081,467,000	55,875,000
BALANCE (shares) at Dec. 31, 2013	394,864,324	'	397,674,350	-2,810,026	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'
Stock-based compensation related activity (shares)	'	'	1,093,535	'	'	'	'	'
Stock-based compensation related activity	55,946,000	'	11,000	'	55,935,000	'	'	'
Issuance of common stock- stock purchase plan Shares	'	'	43,589	'	'	'	'	'
Issuance of common stock- stock purchase plan	2,899,000	'	1,000	'	2,898,000	'	'	'
Issuance of preferred stock, shares	'	6,000,000	'	'	'	'	'	'
Issuance of preferred stock	582,880,000	60,000	'	'	582,820,000	'	'	'
Changes in fair value of cash flow hedges, net of tax	-337,000	'	'	'	'	-455,000	'	118,000
Reclassification of unrealized losses on cash flow hedges to net income, net of tax	1,543,000	'	'	'	'	1,422,000	'	121,000
Foreign currency translation adjustment, net of tax	19,388,000	'	'	'	'	59,333,000	'	-39,945,000
Contributions from noncontrolling interest	7,750,000	'	'	'	'	'	'	7,750,000
Distributions to noncontrolling interest	-291,000	'	'	'	'	'	'	-291,000
Common stock dividends/distributions declared	-262,251,000	'	'	'	'	'	-262,251,000	'
Dividends declared on preferred stock	-4,375,000	'	'	'	'	'	-4,375,000	'
Net income (loss)	414,972,000	'	'	'	'	'	436,930,000	-21,958,000
BALANCE (shares)	6,000,000	6,000,000	'	'	'	'	'	'
BALANCE at Jun. 30, 2014	$4,408,164,000	$60	$3,988,000	($207,740,000)	$5,772,269,000	($250,920,000)	($911,163,000)	$1,670,000
BALANCE (shares) at Jun. 30, 2014	396,001,448	'	398,811,474	-2,810,026	'	'	'	'

Description_of_Business_Basis_

Description of Business, Basis of Presentation and Accounting Policies	6 Months Ended
	Jun. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Description of Business, Basis of Presentation and Accounting Policies	'
	Description of Business, Basis of Presentation and Accounting Policies
	American Tower Corporation is, through its various subsidiaries (collectively, “ATC” or the “Company”), an independent owner, operator and developer of wireless and broadcast communications real estate in the United States, Brazil, Chile, Colombia, Costa Rica, Germany, Ghana, India, Mexico, Panama, Peru, South Africa and Uganda. The Company’s primary business is the leasing of antenna space on multi-tenant communications sites to wireless service providers, radio and television broadcast companies, wireless data and data providers, government agencies and municipalities and tenants in a number of other industries. The Company also manages rooftop and tower sites for property owners, operates in-building and outdoor distributed antenna system (“DAS”) networks, holds property interests under third-party communications sites and provides network development services that primarily support its rental and management operations and the addition of new tenants and equipment on its sites. Since January 1, 2012, the Company has been organized and has qualified as a real estate investment trust (“REIT”) for U.S. federal income tax purposes.
	ATC is a holding company that conducts its operations through its directly and indirectly owned subsidiaries and its joint ventures. ATC’s principal domestic operating subsidiaries are American Towers LLC and SpectraSite Communications, LLC. ATC conducts its international operations primarily through its subsidiary, American Tower International, Inc., which in turn conducts operations through its various international holding and operating subsidiaries and joint ventures.
	The Company holds and operates certain of its assets through one or more taxable REIT subsidiaries (“TRSs”). The use of TRSs enables the Company to continue to engage in certain businesses while complying with REIT qualification requirements and also allows the Company to retain income generated by these businesses for reinvestment without the requirement of distributing those earnings. The businesses that the Company holds through its TRSs primarily include certain of its international operations and a portion of its managed network business.
	As a REIT, the Company generally is not subject to federal income taxes on its income and gains that the Company distributes to its stockholders, including the income derived from leasing space on its towers. However, even as a REIT, the Company remains obligated to pay income taxes on earnings from its TRS operations. In addition, the Company’s international assets and operations, including those designated as direct or indirect qualified REIT subsidiaries or other disregarded entities of a REIT (collectively, “QRSs”), continue to be subject to taxation in the foreign jurisdictions where those assets are held or those operations are conducted.
	The Company may, from time to time, change the election of previously designated TRSs that hold certain of its operations to be treated as QRSs, and may reorganize and transfer certain assets or operations from its TRSs to other subsidiaries, including QRSs. For all periods subsequent to the conversion from a TRS to a QRS, the Company includes the income from the QRSs as part of its REIT taxable income for the purpose of computing the Company’s REIT distribution requirements. During the six months ended June 30, 2014, the Company restructured certain of its German subsidiaries and certain of its domestic TRSs, which included a portion of its network development services segment and indoor DAS networks business, to be treated as QRSs. As of June 30, 2014, in addition to these businesses, the Company’s QRSs include its domestic tower leasing business and most of its operations in Costa Rica, Mexico and Panama.
	The accompanying condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission. The financial information included herein is unaudited; however, the Company believes that all adjustments (consisting primarily 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. 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, 2013.
	Principles of Consolidation and Basis of Presentation—The accompanying condensed consolidated financial statements include the accounts of the Company and those entities in which it has a controlling interest. Investments in entities that the Company does not control are accounted for using the equity or cost method, depending upon the Company’s ability to exercise significant influence over operating and financial policies. All intercompany accounts and transactions have been eliminated.
	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. The significant estimates in the accompanying condensed consolidated financial statements include impairment of long-lived assets (including goodwill), asset retirement obligations, revenue recognition, rent expense, stock-based compensation, income taxes and accounting for business combinations. 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.
	Functional Currency—The functional currency of the Company’s foreign operating subsidiaries is the respective local currency, except for Costa Rica and Panama, where the functional currency is the U.S. Dollar.  All foreign currency assets and liabilities held by the subsidiaries are translated into U.S. Dollars at the exchange rate in effect at the end of the applicable fiscal reporting period and all foreign currency revenues and expenses are translated at the average monthly exchange rates. Translation adjustments are reflected in equity as a component of Accumulated other comprehensive income (loss) (“AOCI”) in the condensed consolidated balance sheets.
	Transactional gains and losses on foreign currency transactions are reflected in Other expense in the condensed consolidated statements of operations.  However, the effect from fluctuations in foreign currency exchange rates on intercompany notes whose payment is not planned or anticipated in the foreseeable future is reflected in AOCI in the condensed consolidated balance sheets.  During the three months ended June 30, 2014, the Company recorded unrealized foreign currency losses of $53.2 million, of which $29.6 million was recorded in AOCI and $23.6 million was recorded in Other expense. During the six months ended June 30, 2014, the Company recorded unrealized foreign currency losses of $68.7 million, of which $43.1 million was recorded in AOCI and $25.6 million was recorded in Other expense.
	Accounting Standards Updates—In April 2014, the Financial Accounting Standards Board (the “FASB”) issued additional guidance on reporting discontinued operations. Under this guidance, only disposals representing a strategic shift in operations would be presented as discontinued operations. This guidance requires expanded disclosure that provides information about the assets, liabilities, income and expenses of discontinued operations. Additionally, the guidance requires additional disclosure for a disposal of a significant part of an entity that does not qualify for discontinued operations reporting. This guidance will be effective for reporting periods beginning on or after December 15, 2014 with early adoption permitted for disposals or classifications of assets as held-for-sale that have not been reported in financial statements previously issued or available for issuance. The Company adopted this guidance during the six months ended June 30, 2014 and the adoption did not have a material effect on the Company’s financial statements.
	In May 2014, the FASB issued new revenue recognition guidance, which requires an entity to recognize revenue in an amount that reflects the consideration to which the entity expects to be entitled in exchange for the transfer of promised goods or services to customers. The standard will replace most existing revenue recognition guidance in GAAP. The amendment will become effective on January 1, 2017, and early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. Leases are not included in the scope of this standard. The Company is evaluating the impact this standard will have on its financial statements.

Prepaid_and_Other_Current_Asse

Prepaid and Other Current Assets	6 Months Ended
	Jun. 30, 2014
Prepaid Expense and Other Assets, Current [Abstract]	'
Prepaid and Other Current Assets	'
	Prepaid and Other Current Assets
	Prepaid and other current assets consists of the following as of (in thousands):
		30-Jun-14		December 31, 2013 (1)
	Prepaid operating ground leases	$	86,700	$	95,580
	Prepaid income tax	62,593		52,612
	Acquisition deposit in escrow	59,024		—
	Unbilled receivables	37,871		25,412
	Prepaid assets	26,693		34,243
	Value added tax and other consumption tax receivables	15,730		77,016
	Other miscellaneous current assets	54,187		56,022
	Balance	$	342,798	$	340,885
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	6 Months Ended
	Jun. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Other Intangible Assets	'
	Goodwill and Other Intangible Assets
	The changes in the carrying value of goodwill for the Company’s business segments are as follows (in thousands):
			Rental and Management						Network				Total
									Development
			Domestic			International			Services
	Balance as of January 1, 2014 (1)		$	3,258,680		$	547,746		$	2,000			$	3,808,426
	Additions		33,671			4,232			—				37,903
	Effect of foreign currency translation		—			8,614			—				8,614
	Other (2)		—			—			(12		)		(12		)
	Balance as of June 30, 2014		$	3,292,351		$	560,592		$	1,988			$	3,854,931
	-1	Balances have been revised to reflect purchase accounting measurement period adjustments.
	-2	Other represents the fair value adjustment to goodwill associated with the Company’s third-party structural analysis business, which was considered held-for-sale at June 30, 2014.
	The Company’s other intangible assets subject to amortization consist of the following as of (in thousands):
					30-Jun-14											December 31, 2013 (1)
			Estimated		Gross			Accumulated				Net Book				Gross		Accumulated			Net Book
			Useful		Carrying			Amortization				Value				Carrying		Amortization			Value
			Lives		Value											Value
			(years)
	Acquired network location (2)		Up to 20		$	2,437,303		$	(869,234	)		$	1,568,069			$	2,419,708	$	(791,359	)	$	1,628,349
	Acquired customer-related intangibles		15-20		6,283,602			(1,307,289		)		4,976,313				6,026,480		(1,170,239		)	4,856,241
	Acquired licenses and other intangibles		20-Mar		6,755			(2,815		)		3,940				6,583		(2,297		)	4,286
	Economic Rights, TV Azteca		70		28,927			(14,560		)		14,367				28,783		(14,229		)	14,554
	Total				$	8,756,587		$	(2,193,898	)		$	6,562,689			$	8,481,554	$	(1,978,124	)	$	6,503,430
	Deferred financing  costs, net (3)		N/A									75,193									76,875
	Other intangible assets, net											$	6,637,882								$	6,580,305
	-1	Balances have been revised to reflect purchase accounting measurement period adjustments.
	-2	Acquired network location intangibles are amortized over the shorter of the term of the corresponding ground lease taking into consideration lease renewal options and residual value or up to 20 years, as the Company considers these intangibles to be directly related to the tower assets.
	-3	Deferred financing costs are amortized over the term of the respective debt instruments to which they relate using the effective interest method. This amortization is included in Interest expense rather than in Depreciation, amortization and accretion expense.
	The acquired network location intangibles represent the value to the Company of the incremental revenue growth that could potentially be obtained from leasing the excess capacity on acquired communications sites. The acquired customer-related intangibles typically represent the value to the Company of customer contracts and relationships in place at the time of an acquisition, including assumptions regarding estimated renewals.
	The Company amortizes its acquired network intangibles and customer-related intangibles on a straight-line basis over their estimated useful lives. As of June 30, 2014, the remaining weighted average amortization period of the Company’s intangible assets, excluding deferred financing costs and the TV Azteca Economic Rights detailed in note 5 to the Company’s consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013, is approximately 16 years. Amortization of intangible assets for the three and six months ended June 30, 2014 was approximately $101.6 million and $204.2 million, respectively, and amortization of intangible assets for the three and six months ended June 30, 2013 was approximately $61.1 million and $120.3 million, respectively. Amortization expense excludes amortization of deferred financing costs, which is included in Interest expense on the condensed consolidated statements of operations. Based on current exchange rates, the Company expects to record amortization expense (excluding amortization of deferred financing costs) as follows over the remaining current year and the next five subsequent years (in millions):
	Fiscal Year
	2014 (remaining year)	$	207.4
	2015	412.5
	2016	409.8
	2017	407.5
	2018	405.4
	2019	403.3
	During the three months ended June 30, 2014, the Company determined that its operations in Panama and its third-party structural analysis business were held-for-sale. The Company assessed the carrying value of its operations in Panama, which are included in its international rental and management segment, and concluded that the value is expected to be recoverable and, accordingly, no impairment charge was recorded. The Company recorded an impairment charge of $4.1 million during the three and six months ended June 30, 2014 for its third-party structural analysis business, which is included in its network development services segment, related to the write down of its intangible assets and goodwill to fair value. For additional information on assets held-for-sale, see note 7.

Accrued_Expenses

Accrued Expenses	6 Months Ended
	Jun. 30, 2014
Accrued Liabilities, Current [Abstract]	'
Accrued Expenses	'
	Accrued Expenses
	Accrued expenses consists of the following as of (in thousands):
		30-Jun-14		December 31, 2013 (1)
	Accrued construction costs	$	72,878	$	52,446
	Accrued property and real estate taxes	65,533		54,529
	Payroll and related withholdings	35,484		50,843
	Accrued rent	34,002		28,456
	Other accrued expenses	214,717		228,801
	Balance	$	422,614	$	415,075
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Longterm_Obligations

Long-term Obligations	6 Months Ended
	Jun. 30, 2014
Securities Financing Transactions [Abstract]	'
Long-Term Obligations	'
	Long-Term Obligations
	Current portion of long-term obligations—In connection with its acquisition of MIP Tower Holdings LLC (“MIPT”) (see note 14) on October 1, 2013, the Company assumed approximately $1.49 billion principal amount of existing indebtedness under six series, consisting of eleven separate classes, of Secured Tower Revenue Notes issued by certain subsidiaries of Global Tower Partners (“GTP”) in several securitization transactions (the “GTP Notes”). The Series 2010-1 Class C Notes and the Series 2010-1 Class F Notes (together, the “Series 2010-1 Notes”) have an aggregate principal amount outstanding of $250.0 million and an anticipated repayment date of February 15, 2015. As a result, the aggregate principal amount of $250.0 million and the unamortized premium of $3.4 million of the Series 2010-1 Notes is reflected in Current portion of long-term obligations in the condensed consolidated balance sheets.
	In addition, the Company’s 4.625% senior unsecured notes mature on April 1, 2015. As a result, the aggregate principal amount of $600.0 million, net of unamortized discount of $0.1 million, is reflected in Current portion of long-term obligations in the condensed consolidated balance sheets.
	Costa Rica Loan—In connection with its acquisition of MIPT, the Company assumed $32.6 million of secured debt in Costa Rica (the “Costa Rica Loan”), which it repaid in full in February 2014.
	Colombian Bridge Loans—In connection with the acquisition of communications sites in Colombia, one of the Company’s Colombian subsidiaries entered into six Colombian Peso (“COP”) denominated bridge loans for an aggregate principal amount of 108.0 billion COP (approximately $57.4 million). As of June 30, 2014, the interest rate was 7.86% and the maturity date of the loans was July 31, 2014. In July 2014, the maturity date of the loans was extended to August 31, 2014.
	Mexican Loan—In connection with the acquisition of towers in Mexico from NII Holdings, Inc. (“NII”) during the fourth quarter of 2013, one of the Company’s Mexican subsidiaries entered into a 5.2 billion Mexican Peso (“MXN”) denominated unsecured bridge loan (the “Mexican Loan”) and subsequently borrowed approximately 4.9 billion MXN (approximately $374.7 million at the date of borrowing). The Mexican subsidiary’s ability to draw down the remaining 0.3 billion MXN under the Mexican Loan expired in February 2014. During the six months ended June 30, 2014, the Mexican subsidiary repaid 1.1 billion MXN (approximately $80.4 million on the date of repayment) of the outstanding indebtedness with cash on hand. As of June 30, 2014, the Company had 3.9 billion MXN (approximately $298.6 million) outstanding under the Mexican Loan, which is reflected in Current portion of long-term obligations in the condensed consolidated balance sheets.
	Colombian Loan—In connection with the establishment of the Company’s joint venture with Millicom International Cellular SA (“Millicom”) and the acquisition of certain communications sites in Colombia, ATC Colombia B.V., a majority owned subsidiary of the Company, entered into a U.S. Dollar-denominated shareholder loan agreement (the “Colombian Loan”), as the borrower, with the Company’s wholly owned subsidiary (the “ATC Colombian Subsidiary”), and a wholly owned subsidiary of Millicom (the “Millicom Subsidiary”), as the lenders. The portion of the Colombian Loan made by the ATC Colombian Subsidiary is eliminated in consolidation, and the portion of the Colombian Loan made by the Millicom Subsidiary is reported as outstanding debt. During the six months ended June 30, 2014, the joint venture borrowed an additional $3.0 million under the Colombian Loan, which was subsequently converted from debt to equity, and the balance as of June 30, 2014 is $35.1 million. In July 2014, the Company purchased Millicom’s interest in the joint venture and the Colombian Loan using proceeds from borrowings under the Company’s $2.0 billion multi-currency senior unsecured revolving credit facility. As a result, all amounts outstanding under the Colombian Loan will be eliminated in consolidation.
	Richland Notes—In connection with its acquisition of entities holding a portfolio of communications sites from Richland Properties LLC and other related entities (“Richland”) (see note 14), the Company assumed approximately $196.5 million of secured debt (the “Richland Notes”) and recorded a fair value premium of $5.5 million upon acquisition.  In June 2014, the Company repaid the outstanding indebtedness, paid prepayment consideration and wrote-off the unamortized premium associated with the fair value adjustment.  As a result, the Company recorded a Loss on retirement of long-term obligations in the accompanying condensed consolidated statements of operations of $1.3 million.
	2012 Credit Facility—During the six months ended June 30, 2014, the Company repaid $88.0 million of outstanding indebtedness under its $1.0 billion senior unsecured revolving credit facility (the “2012 Credit Facility”) with net proceeds from a registered public offering of $250.0 million aggregate principal amount of reopened 3.40% senior unsecured notes due 2019 and $500.0 million aggregate principal amount of reopened 5.00% senior unsecured notes due 2024. As of June 30, 2014, the Company has no amounts outstanding under the 2012 Credit Facility and $7.5 million of undrawn letters of credit. The Company maintains the ability to draw down and repay amounts under the 2012 Credit Facility in the ordinary course.
	The 2012 Credit Facility matures on January 31, 2017, does not require amortization of principal and may be paid prior to maturity in whole or in part at the Company’s option without penalty or premium. The current margin over the London Interbank Offered Rate (“LIBOR”) that the Company would incur (should it choose LIBOR) on borrowings is 1.625%, and the current commitment fee on the undrawn portion of the 2012 Credit Facility is 0.225%.
	2013 Credit Facility—During the six months ended June 30, 2014, the Company repaid $1.4 billion of outstanding indebtedness under its $2.0 billion multi-currency senior unsecured revolving credit facility (the “2013 Credit Facility”) using (i) proceeds from a registered public offering of $250.0 million aggregate principal amount of reopened 3.40% senior unsecured notes due 2019 and $500.0 million aggregate principal amount of reopened 5.00% senior unsecured notes due 2024, (ii) proceeds from the issuance of mandatory convertible preferred stock in May 2014 (see note 11) and (iii) cash on hand. During the six months ended June 30, 2014, the Company borrowed an additional $360.0 million under the 2013 Credit Facility, which it primarily used to fund recent acquisitions, including the acquisition from Richland, and the repayment of the Richland Notes.
	As of June 30, 2014, the Company has $783.0 million outstanding under the 2013 Credit Facility and approximately $3.2 million of undrawn letters of credit. In July 2014, the Company borrowed a net amount of $140.0 million under the 2013 Credit Facility, a portion of which it used to purchase Millicom’s interest in the Colombian joint venture and the Colombian Loan. The 2013 Credit Facility includes an expansion option allowing the Company to request additional commitments of up to $750.0 million, including in the form of a term loan. The Company maintains the ability to draw down and repay amounts under the 2013 Credit Facility in the ordinary course.
	The 2013 Credit Facility matures on June 28, 2018 and includes two one-year renewal periods at the Company’s option. The 2013 Credit Facility does not require amortization of principal and may be paid prior to maturity in whole or in part at the Company’s option without penalty or premium. The current margin over LIBOR that the Company incurs on borrowings is 1.250%, and the current commitment fee on the undrawn portion of the 2013 Credit Facility is 0.150%.
	Short-Term Credit Facility—On September 20, 2013, the Company entered into a $1.0 billion senior unsecured revolving credit facility (the “Short-Term Credit Facility”). The Short-Term Credit Facility does not require amortization of principal and may be repaid prior to maturity in whole or in part at the Company’s option without penalty or premium. The Company may reduce or terminate the unutilized portion of the commitments under the Short-Term Credit Facility in whole or in part without penalty.
	The Short-Term Credit Facility matures on September 19, 2014. The current margin over LIBOR that the Company would incur (should it choose LIBOR) on borrowings is 1.250%, and the current commitment fee on the undrawn portion is 0.150%. As of June 30, 2014, the Company has no amounts outstanding under the Short-Term Credit Facility and maintains the ability to draw down and repay amounts under the Short-Term Credit Facility in the ordinary course.
	2013 Term Loan—On October 29, 2013, the Company entered into a $1.5 billion unsecured term loan (the “2013 Term Loan”), which includes an expansion option allowing the Company to request additional commitments of up to $500.0 million. The 2013 Term Loan matures on January 3, 2019, and the current interest rate is LIBOR plus 1.250%.
	Senior Notes Offering—On January 10, 2014, the Company completed a registered public offering through a reopening of its (i) 3.40% senior unsecured notes due 2019 (the “3.40% Notes”), in an aggregate principal amount of $250.0 million and (ii) 5.00% senior unsecured notes due 2024 (the “5.00% Notes”), in an aggregate principal amount of $500.0 million. The net proceeds from the offering were approximately $763.8 million, after deducting commissions and estimated expenses. As a result, the aggregate outstanding principal amount of each of the 3.40% Notes and the 5.00% Notes is $1.0 billion.
	The Company used a portion of the proceeds, together with cash on hand, to repay $88.0 million of outstanding indebtedness under the 2012 Credit Facility and $710.0 million of outstanding indebtedness under the 2013 Credit Facility.
	The reopened 3.40% Notes issued on January 10, 2014 have identical terms as, are fungible with and are part of a single series of senior debt securities with the 3.40% Notes issued on August 19, 2013. The reopened 5.00% Notes issued on January 10, 2014 have identical terms as, are fungible with and are part of a single series of senior debt securities with the 5.00% Notes issued on August 19, 2013.
	The 3.40% Notes mature on February 15, 2019 and bear interest at a rate of 3.40% per annum. The 5.00% Notes mature on February 15, 2024 and bear interest at a rate of 5.00% per annum. Accrued and unpaid interest on the 3.40% Notes and the 5.00% Notes is payable in U.S. Dollars semi-annually in arrears on February 15 and August 15 of each year, beginning on February 15, 2014. Interest on the 3.40% Notes and the 5.00% Notes accrues from August 19, 2013 and is computed on the basis of a 360-day year comprised of twelve 30-day months.
	The Company may redeem the 3.40% Notes or the 5.00% Notes at any time at a redemption price equal to 100% of the principal amount, plus a make-whole premium, together with accrued interest to the redemption date. If the Company undergoes a change of control and ratings decline, each as defined in the supplemental indenture, the Company may be required to repurchase all of the 3.40% Notes and the 5.00% Notes at a purchase price equal to 101% of the principal amount of the 3.40% Notes and the 5.00% Notes, plus accrued and unpaid interest (including additional interest, if any), up to but not including the repurchase date. The 3.40% Notes and the 5.00% Notes rank equally with all of the Company’s other senior unsecured debt and are structurally subordinated to all existing and future indebtedness and other obligations of its subsidiaries.
	The supplemental indenture contains certain covenants that restrict the Company’s ability to merge, consolidate or sell assets and its (together with its subsidiaries’) ability to incur liens. These covenants are subject to a number of exceptions, including that the Company and its subsidiaries may incur certain liens on assets, mortgages or other liens securing indebtedness, if the aggregate amount of such liens does not exceed 3.5x Adjusted EBITDA, as defined in the supplemental indenture.

Derivative_Financial_Instrumen

Derivative Financial Instruments	6 Months Ended
	Jun. 30, 2014
Summary of Derivative Instruments [Abstract]	'
Derivative Financial Instruments	'
	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. From time to time, the Company enters into interest rate protection agreements to manage exposure to 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.
	If a derivative is designated as a cash flow hedge, the effective portion of changes in the fair value of the derivative is recorded in AOCI and is recognized in the results of operations when the hedged item affects earnings. The ineffective portion of changes in the fair value of cash flow hedges is 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.
	Certain of the Company’s foreign subsidiaries have entered into interest rate swap agreements to manage exposure to variability in interest rates on debt in Colombia and South Africa and these interest rate swap agreements have been designated as cash flow hedges.
	South Africa
	One of the Company’s South African subsidiaries has fifteen interest rate swap agreements outstanding, which mature on the earlier of termination of the underlying debt or March 31, 2020. The interest rate swap agreements provide that the Company pay a fixed interest rate ranging from 6.09% to 7.83% and receive variable interest at the three-month Johannesburg Interbank Agreed Rate (JIBAR) over the term of the interest rate swap agreements. The notional value is reduced in accordance with the repayment schedule under the related credit agreement.
	Colombia
	One of the Company’s Colombian subsidiaries has an interest rate swap agreement outstanding, which matures on the earlier of termination of the underlying debt or November 30, 2020. The interest rate swap agreement provides that the Company pay a fixed interest rate of 5.78% and receive variable interest at the three-month Inter-bank Rate (IBR) over the term of the interest rate swap agreement. The notional value is reduced in accordance with the repayment schedule under the related credit agreement.
	Costa Rica
	One of the Company’s Costa Rican subsidiaries had three interest rate swaps agreements, which were terminated upon repayment of the Costa Rica Loan in February 2014.
	The notional amount and fair value of the interest rate swap agreements are as follows (in thousands):
		30-Jun-14					31-Dec-13
		Local		USD			Local		USD
	South Africa (ZAR)
	Notional	457,079		42,969			469,354		44,732
	Fair Value	3,773		355			939		90
	Colombia (COP)
	Notional	100,743,750		53,553			101,250,000		52,547
	Fair Value	(1,625,102	)	(864	)		(3,000,236	)	(1,557	)
	Costa Rica (USD)
	Notional	—		—			N/A		42,000
	Fair Value	—		—			N/A		(628	)
	As of June 30, 2014 and December 31, 2013, the South African interest rate swap agreements were in an asset position and were included in Notes receivable and other non-current assets on the condensed consolidated balance sheets. The Colombian interest rate swap agreement was in a liability position and was included in Other non-current liabilities on the condensed consolidated balance sheets.
	During the three months ended June 30, 2014 and 2013, the interest rate swap agreements had the following impact on the Company’s condensed consolidated financial statements (in thousands):
	Three Months Ended June 30,	Gain(Loss) Recognized in Other Comprehensive Income - Effective Portion		Gain(Loss)		Location of Gain(Loss) Reclassified from AOCI into Income- Effective Portion		Gain(Loss) Recognized		Location of Gain(Loss) Recognized in Income -
				Reclassified from				in Income - Ineffective Portion		Ineffective Portion
				AOCI into
				Income -
				Effective Portion
	2014	$226		($670)		Interest Expense		N/A		N/A
	2013	$4,138		($704)		Interest Expense		N/A		N/A
	During the six months ended June 30, 2014 and 2013, the interest rate swap agreements had the following impact on the Company’s condensed consolidated financial statements (in thousands):
	Six Months Ended June 30,	Gain(Loss) Recognized in Other Comprehensive Income - Effective Portion		Gain(Loss)		Location of Gain(Loss) Reclassified from AOCI into Income- Effective Portion		Gain(Loss) Recognized		Location of Gain(Loss) Recognized in Income -
				Reclassified from				in Income - Ineffective Portion		Ineffective Portion
				AOCI into
				Income -
				Effective Portion
	2014	($361)		($1,639)		Interest Expense		N/A		N/A
	2013	$3,205		($1,312)		Interest Expense		N/A		N/A
	As of June 30, 2014, approximately $0.7 million related to derivatives designated as cash flow hedges and recorded in AOCI is expected to be reclassified into earnings in the next twelve months.
	For additional information on the Company’s interest rate swap agreements, see notes 7 and 8.

Fair_Value_Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements
	The Company determines the fair value 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 (in thousands):
		June 30, 2014
		Fair Value Measurements Using								Assets/Liabilities
		Level 1		Level 2				Level 3		at Fair Value
	Assets:
	Short-term investments (1)			$	15,298					$	15,298
	Interest rate swap agreements			$	355					$	355
	Liabilities:
	Acquisition-related contingent consideration							$	31,025	$	31,025
	Interest rate swap agreements			$	864					$	864
		31-Dec-13
		Fair Value Measurements Using								Assets/Liabilities
		Level 1		Level 2				Level 3		at Fair Value
	Assets:
	Short-term investments (1)			$	18,612					$	18,612
	Interest rate swap agreements			$	90					$	90
	Liabilities:
	Acquisition-related contingent consideration							$	31,890	$	31,890
	Interest rate swap agreements			$	2,185					$	2,185
	-1	Consists of highly liquid investments with original maturities in excess of three months.
	Interest Rate Swap Agreements
	The fair value of the Company’s interest rate swap agreements is determined using pricing models with inputs that are observable in the market or can be derived principally from, or corroborated by, observable market data. Fair valuations of the interest rate swap agreements reflect the value of the instrument including the values associated with counterparty risk, the Company’s own credit standing and the value of the net credit differential between the counterparties to the derivative contract.
	Acquisition-Related Contingent Consideration
	The Company may be required to pay additional consideration under certain agreements for the acquisition of communications sites if specific conditions are met or events occur. In Colombia and Ghana, the Company may be required to pay additional consideration upon the conversion of certain barter agreements with other wireless carriers to cash-paying lease agreements. In addition, in Costa Rica, Panama and the United States, the Company may be required to pay additional consideration if certain pre-designated tenant leases commence during a specified period of time.
	Acquisition-related contingent consideration is initially measured and recorded at fair value as an element of consideration paid in connection with an acquisition with subsequent adjustments recognized in Other operating expenses in the condensed consolidated statements of operations. The Company determines the fair value of acquisition-related contingent consideration, and any subsequent changes in fair value using a discounted probability-weighted approach. This approach takes into consideration Level 3 unobservable inputs including probability assessments of expected future cash flows over the period in which the obligation is expected to be settled and applies a discount factor that captures the uncertainties associated with the obligation. Changes in these unobservable inputs could significantly impact the fair value of the liabilities recorded in the accompanying condensed consolidated balance sheets and adjustments recorded in the condensed consolidated statements of operations.
	As of June 30, 2014, the Company estimates that the value of all potential acquisition-related contingent consideration required payments to be between zero and $44.6 million. During the three months ended June 30, 2014 and 2013, the fair value of the contingent consideration changed as follows (in thousands):
		2014				2013
	Balance as of April 1	$	31,342			$	25,201
	Additions	406				313
	Payments	(674		)		(1,033		)
	Change in fair value	(952		)		(2,007		)
	Foreign currency translation adjustment	903				(1,256		)
	Balance as of June 30	$	31,025			$	21,218
	During the six months ended June 30, 2014 and 2013, the fair value of the contingent consideration changed as follows (in thousands):
		2014				2013
	Balance as of January 1	$	31,890			$	23,711
	Additions	406				478
	Payments	(1,289		)		(4,222		)
	Change in fair value	(370		)		3,307
	Foreign currency translation adjustment	388				(2,056		)
	Balance as of June 30	$	31,025			$	21,218
	Items Measured at Fair Value on a Nonrecurring Basis
	Assets held and used—The Company’s long-lived assets are measured at fair value on a nonrecurring basis using Level 3 inputs. During the three and six months ended June 30, 2014, the Company did not record any asset impairment charges and during the three and six months ended June 30, 2013, the Company recorded an asset impairment charge of $0.1 million.
	Assets held-for-sale—During the three months ended June 30, 2014, based on a strategic review of the international rental and management segment and components of the network development services segment, the Company determined that its operations in Panama and its third-party structural analysis business were held-for-sale.
	As of June 30, 2014, the net carrying value of the assets and liabilities held-for-sale in Panama is $15.1 million, primarily including $8.0 million of Property and equipment, net and $5.6 million of Other intangible assets, net. The carrying value approximates fair value and, as a result, the Company did not record any impairment charges during the three and six months ended June 30, 2014.
	As of June 30, 2014, the carrying value of the assets held-for-sale related to the Company’s third-party structural analysis business is $2.4 million of Other intangible assets, net, which reflects an impairment charge of $4.1 million related to the write down of intangibles and goodwill to fair value. The Company completed the sale of this business in July 2014.
	The impairment charges for both assets held and used and assets held-for-sale are recorded in Other operating expenses in the accompanying condensed consolidated statements of operations. These adjustments were determined by comparing the estimated net proceeds from sale of assets or the projected future discounted cash flows to be provided from the long-lived assets (calculated using Level 3 inputs) to the asset’s carrying value. There were no other items measured at fair value on a nonrecurring basis during the six months ended June 30, 2014.
	Fair Value of Financial Instruments—The carrying value of the Company’s financial instruments that reasonably approximate fair value at June 30, 2014 and December 31, 2013 includes cash and cash equivalents, restricted cash, accounts receivable and accounts payable. The Company’s estimates of fair value of its long-term obligations, including the current portion, are based primarily upon reported market values. For long-term debt not actively traded, fair value was estimated using either indicative price quotes or a discounted cash flow analysis using rates for debt with similar terms and maturities. As of June 30, 2014, the carrying value and fair value of long-term obligations, including the current portion, are $14.0 billion and $14.5 billion, respectively, of which $9.2 billion was measured using Level 1 inputs and $5.3 billion was measured using Level 2 inputs. As of December 31, 2013, the carrying value and fair value of long-term obligations, including the current portion, were $14.5 billion and $14.7 billion, respectively, of which $8.6 billion was measured using Level 1 inputs and $6.1 billion was measured using Level 2 inputs.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'
Accumulated Other Comprehensive Loss	'
	Accumulated Other Comprehensive Loss
	The changes in Accumulated other comprehensive loss for the three months ended June 30, 2014 and 2013 are as follows (in thousands):
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of April 1, 2014	$	(1,970	)	$	(2,829	)	$	(267,611	)	$	(272,410	)
	Other comprehensive income before reclassifications, net of tax	325			—			20,622			20,947
	Amounts reclassified from accumulated other comprehensive loss, net of tax	344			199			—			543
	Net current-period other comprehensive income	669			199			20,622			21,490
	Balance as of June 30, 2014	$	(1,301	)	$	(2,630	)	$	(246,989	)	$	(250,920	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of less than $0.1 million is included in income tax expense for the three months ended June 30, 2014.
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of April 1, 2013	$	(5,162	)	$	(3,628	)	$	(149,253	)	$	(158,043	)
	Other comprehensive income (loss) before reclassifications, net of tax	3,570			—			(120,394		)	(116,824		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	410			201			—			611
	Net current-period other comprehensive income (loss)	3,980			201			(120,394		)	(116,213		)
	Balance as of June 30, 2013	$	(1,182	)	$	(3,427	)	$	(269,647	)	$	(274,256	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of less than $0.1 million is included in income tax expense for the three months ended June 30, 2013.
	The changes in Accumulated other comprehensive loss for the six months ended June 30, 2014 and 2013 are as follows (in thousands):
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of January 1, 2014	$	(1,869	)	$	(3,029	)	$	(306,322	)	$	(311,220	)
	Other comprehensive (loss) income before reclassifications, net of tax	(455		)	—			59,333			58,878
	Amounts reclassified from accumulated other comprehensive loss, net of tax	1,023			399			—			1,422
	Net current-period other comprehensive income	568			399			59,333			60,300
	Balance as of June 30, 2014	$	(1,301	)	$	(2,630	)	$	(246,989	)	$	(250,920	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of $0.1 million is included in income tax expense for the six months ended June 30, 2014.
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of January 1, 2013	$	(4,358	)	$	(3,827	)	$	(175,162	)	$	(183,347	)
	Other comprehensive income (loss) before reclassifications, net of tax	2,456			—			(94,485		)	(92,029		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	720			400			—			1,120
	Net current-period other comprehensive income (loss)	3,176			400			(94,485		)	(90,909		)
	Balance as of June 30, 2013	$	(1,182	)	$	(3,427	)	$	(269,647	)	$	(274,256	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of $0.1 million is included in income tax expense for the six months ended June 30, 2013.

Income_Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2014
Income Tax Expense (Benefit), Continuing Operations [Abstract]	'
Income Taxes	'
	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 tax rate is determined. The Company reorganized to qualify as a REIT for the taxable year commencing January 1, 2012. As a REIT, the Company continues to be subject to income taxes on the income of its TRSs, and taxation in foreign jurisdictions where it conducts international operations. Under the provisions of the Internal Revenue Code of 1986, as amended, the Company may deduct amounts distributed to stockholders against the income generated in its QRSs. The Company is able to offset income in both its TRSs and QRSs by utilizing their respective net operating losses. In addition, MIPT has been organized and has qualified as a REIT. For so long as MIPT continues to elect separate REIT status, it is independently subject to, and must comply with, the same REIT requirements that the Company must satisfy in order to qualify as a REIT, together with all other rules applicable to REITs.
	The Company provides valuation allowances if, based on the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. Management assesses the available positive and negative evidence to estimate if sufficient future taxable income will be generated to use the existing deferred tax assets.
	As of June 30, 2014 and December 31, 2013, the total amount of unrecognized tax benefits that would impact the effective tax rate, if recognized, was approximately $37.7 million and $31.1 million, respectively. The increase in the amount of unrecognized tax benefits during the three and six months ended June 30, 2014 is primarily attributable to the additions to the Company’s existing tax positions and fluctuations in foreign currency exchange rates. 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 14 to the Company’s consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013. The impact of the amount of such changes to previously recorded uncertain tax positions could range from zero to $14.6 million.
	The Company recorded penalties and income tax-related interest expense during the three and six months ended June 30, 2014 of $1.9 million and $3.2 million, respectively, and during the three and six months ended June 30, 2013 of $1.3 million and $2.6 million, respectively. As of June 30, 2014 and December 31, 2013, the total amount of accrued penalties and income tax-related interest included in Other non-current liabilities in the condensed consolidated balance sheets was $34.8 million and $30.9 million, respectively.

StockBased_Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2014
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]	'
Stock-Based Compensation	'
	Stock-Based Compensation
	The Company recognized stock-based compensation expense during the three and six months ended June 30, 2014 of $18.8 million and $43.4 million, respectively, and stock-based compensation expense during the three and six months ended June 30, 2013 of $17.1 million and $38.1 million, respectively. Stock-based compensation expense for the three and six months ended June 30, 2013 included $1.1 million related to the modification of the vesting and exercise terms for certain employees’ equity awards. The Company capitalized stock-based compensation expense of $0.4 million during each of the three months ended June 30, 2014 and 2013, and $0.8 million during each of the six months ended June 30, 2014 and 2013, as property and equipment.
	Summary of Stock-Based Compensation Plans—The Company maintains equity incentive plans that provide for the grant of stock-based awards to its directors, officers and employees. The 2007 Equity Incentive Plan (the “2007 Plan”) provides for the grant of non-qualified and incentive stock options, as well as restricted stock units, restricted stock and other stock-based awards. Exercise prices in the case of non-qualified and incentive stock options are not less than the fair value of the underlying common stock on the date of grant. Equity awards typically vest ratably over various periods, generally four years, and stock options generally expire ten years from the date of grant. As of June 30, 2014, the Company has the ability to grant stock-based awards with respect to an aggregate of 14.2 million shares of common stock under the 2007 Plan.
	The Company’s Compensation Committee adopted a death, disability and retirement benefits program in connection with equity awards granted on or after January 1, 2013, which provides for accelerated vesting and extended exercise periods of stock options and restricted stock units upon an employee’s death or permanent disability, or upon an employee’s qualified retirement, provided certain eligibility criteria are met. Due to the accelerated recognition of stock-based compensation expense related to awards granted to retirement eligible employees, the Company recognized an incremental $1.2 million and $9.7 million of stock-based compensation expense during the three and six months ended June 30, 2014, respectively, and an incremental $0.6 million and $7.3 million of stock-based compensation expense during the three and six months ended June 30, 2013, respectively.
	Stock Options—The Company’s option activity for the six months ended June 30, 2014 is as follows:
		Number of
		Options
	Outstanding as of January 1, 2014	6,106,171
	Granted	1,858,633
	Exercised	(627,037	)
	Forfeited	(100,830	)
	Expired	(33,188	)
	Outstanding as of June 30, 2014	7,203,749
	The fair value of each option granted during the six months ended June 30, 2014 is estimated on the date of grant using the Black-Scholes option pricing model based on the assumptions noted in the table below:
	Range of risk-free interest rate		1.46% - 1.74%
	Weighted average risk-free interest rate		1.64	%
	Expected life of option grants		4.5 years
	Range of expected volatility of underlying stock price		22.45% - 23.35%
	Weighted average expected volatility of underlying stock price		23.09	%
	Expected annual dividend yield		1.5	%
	The weighted average grant date fair value per share during the six months ended June 30, 2014 was $14.84. As of June 30, 2014, total unrecognized compensation expense related to unvested stock options is $45.2 million and is expected to be recognized over a weighted average period of approximately two years.
	Restricted Stock Units—The following table summarizes the Company’s restricted stock unit activity during the six months ended June 30, 2014:
		Number of
		Units
	Outstanding as of January 1, 2014	1,840,137
	Granted	786,584
	Vested	(689,501	)
	Forfeited	(91,769	)
	Outstanding as of June 30, 2014	1,845,451
	As of June 30, 2014, total unrecognized compensation expense related to unvested restricted stock units granted under the 2007 Plan is $102.7 million and is expected to be recognized over a weighted average period of approximately two years.
	Employee Stock Purchase Plan—The Company maintains an employee stock purchase plan (“ESPP”) for all eligible employees as described in note 15 to the Company’s consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013. Under the ESPP, shares of the Company’s common stock may be purchased on the last day of each bi-annual offering period at a 15% discount of the lower of the closing market value on the first or last day of such offering period. 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, 2014, employee contributions were accumulated to purchase an estimated 44,000 shares under the ESPP.
	Key assumptions used to apply the Black-Scholes pricing model for shares purchased through the ESPP during the six months ended June 30, 2014, which resulted in a fair value per share of $14.35, are as follows:
	Approximate risk-free interest rate	0.11	%
	Expected life of shares	6 months
	Expected volatility of underlying stock price over the option period	16.59	%
	Expected annual dividend yield	1.5	%

Equity

Equity	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Equity	'
	Equity
	5.25% Mandatory Convertible Preferred Stock Offering—On May 12, 2014, the Company completed a registered public offering of 6,000,000 shares of its 5.25% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share (the “Mandatory Convertible Preferred Stock”).  The net proceeds of the offering were $582.9 million after deducting commissions and estimated expenses. The Company used the net proceeds from this offering to fund recent acquisitions, including the acquisition from Richland, initially funded by indebtedness incurred under the 2013 Credit Facility.
	Unless converted earlier, each share of the Mandatory Convertible Preferred Stock will automatically convert on May 15, 2017, into between 0.9174 and 1.1468 shares of common stock, depending on the applicable market value of the common stock and subject to anti-dilution adjustments. Subject to certain restrictions, at any time prior to May 15, 2017, holders of the Mandatory Convertible Preferred Stock may elect to convert all or a portion of their shares into common stock at the minimum conversion rate then in effect.
	Dividends on shares of Mandatory Convertible Preferred Stock are payable on a cumulative basis when, as and if declared by the Company’s Board of Directors (or an authorized committee thereof) at an annual rate of 5.25% on the liquidation preference of $100.00 per share, on February 15, May 15, August 15 and November 15 of each year, commencing on August 15, 2014 to, and including, May 15, 2017. The Company may pay dividends in cash or, subject to certain limitations, in shares of common stock or any combination of cash and shares of common stock. The terms of the Mandatory Convertible Preferred Stock provide that, unless full cumulative dividends have been paid or set aside for payment on all outstanding Mandatory Convertible Preferred Stock for all prior dividend periods, no dividends may be declared or paid on common stock.
	Stock Repurchase Program—In March 2011, the Board of Directors approved a stock repurchase program, pursuant to which the Company is authorized to purchase up to $1.5 billion of common stock (the “2011 Buyback”). On September 6, 2013, the Company temporarily suspended repurchases in connection with its acquisition of MIPT.
	Under the 2011 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 makes purchases 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.
	The Company continues to manage the pacing of the remaining $1.1 billion under the 2011 Buyback in response to general market conditions and other relevant factors, including its financial policies. 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 credit facilities. Purchases under the 2011 Buyback are subject to the Company having available cash to fund repurchases.
	Sales of Equity Securities—The Company receives proceeds from sales of its equity securities pursuant to its ESPP and upon exercise of stock options granted under its equity incentive plans. During the six months ended June 30, 2014, the Company received an aggregate of $30.7 million in proceeds upon exercises of stock options and from its ESPP.
	Distributions—During the six months ended June 30, 2014, the Company declared the following cash distributions:
		Declaration Date	Payment Date	Record Date	Distribution per share		Aggregate Payment Amount (in millions)
	Common stock	March 6, 2014	April 25, 2014	April 10, 2014	$	0.32	$	126.6
	Common stock	May 21, 2014	July 16, 2014	June 17, 2014	$	0.34	$	134.6
	Preferred stock	May 21, 2014	15-Aug-14	1-Aug-14	$	1.3563	$	8.1
	The Company accrues distributions on unvested restricted stock unit awards granted subsequent to January 1, 2012, which are payable upon vesting. As of June 30, 2014, the amount accrued for distributions payable related to unvested restricted stock units is $2.3 million. During the six months ended June 30, 2014, the Company paid $0.6 million of distributions upon the vesting of restricted stock units.
	To maintain its REIT status, the Company expects to continue paying regular distributions, the amount, timing and frequency of which will be determined, and subject to adjustment, by the Company’s Board of Directors.

Earnings_Per_Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	Basic net income per common share represents net income attributable to American Tower Corporation common stockholders divided by the weighted average number of common shares outstanding during the period. Diluted net income per common share represents net income attributable to American Tower Corporation common stockholders divided by the weighted average number of common shares outstanding during the period and any dilutive common share equivalents, including shares issuable (i) upon the vesting of restricted stock awards, (ii) upon exercise of stock options and (iii) upon conversion of the Mandatory Convertible Preferred Stock (see note 11). Dilutive common share equivalents also include the dilutive impact of the Verizon transaction (see note 13).
	The Company uses the treasury stock method to calculate the effect of its outstanding restricted stock awards and stock options and uses the if-converted method to calculate the effect of its outstanding Mandatory Convertible Preferred Stock. The following table sets forth basic and diluted net income per common share computational data for the three and six months ended June 30, 2014 and 2013 (in thousands, except per share data):
		Three Months Ended June 30,							Six Months Ended June 30,
		2014				2013			2014			2013
	Net income attributable to American Tower Corporation stockholders	$	234,431			$	99,821		$	436,930		$	271,228
	Dividends declared on preferred stock	(4,375		)		—			(4,375		)	—
	Net income attributable to American Tower Corporation common stockholders	230,056				99,821			432,555			271,228
	Basic weighted average common shares outstanding	395,872				395,420			395,511			395,330
	Dilutive securities	3,716				4,038			3,941			4,329
	Diluted weighted average common shares outstanding	399,588				399,458			399,452			399,659
	Basic net income attributable to American Tower Corporation common stockholders per common share	$	0.58			$	0.25		$	1.09		$	0.69
	Diluted net income attributable to American Tower Corporation common stockholders per common share	$	0.58			$	0.25		$	1.08		$	0.68
	Shares Excluded From Dilutive Effect
	The following shares were not included in the computation of diluted earnings per share because the effect would be anti-dilutive (in thousands, on a weighted average basis):
		Three Months Ended June 30,						Six Months Ended June 30,
		2014			2013			2014		2013
	Restricted stock awards	3			—			1		—
	Stock options	2,497			1,229			2,342		860
	Preferred stock (1)	3,733			—			1,877		—
	(1)     Issued on May 12, 2014.

Commitments_and_Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Litigation
	The Company periodically becomes involved in various claims, lawsuits and proceedings that are incidental to its business. In the opinion of Company management, after consultation with counsel, 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.
	TriStar Litigation—The Company was involved in several lawsuits against TriStar Investors LLP and its affiliates (“TriStar”) in various states regarding single tower sites where TriStar had taken land interests under the Company’s owned or managed sites and the Company believes TriStar induced the landowner to breach obligations to the Company.  In addition, on February 16, 2012, TriStar brought a federal action against the Company in the United States District Court for the Northern District of Texas (the “District Court”), in which TriStar principally alleged that the Company made misrepresentations to landowners when competing with TriStar for land under the Company’s owned or managed sites.  On January 22, 2013, the Company filed an amended answer and counterclaim against TriStar and certain of its employees, denying Tristar’s claims and asserting that TriStar engaged in a pattern of unlawful activity, including: (i) entering into agreements not to compete for land under certain towers; and (ii) making widespread misrepresentations to landowners regarding both TriStar and the Company.  Both parties sought injunctive relief that would prohibit the other party from making certain statements when interacting with landowners, as well as significant damages. On April 3, 2014, the District Court ruled on the parties’ cross-motions for summary judgment, permitting both parties’ claims of misrepresentation to proceed to trial, as well as related state law actions, and dismissing certain of the parties’ other claims. Pursuant to a Settlement Agreement dated July 9, 2014, all pending state and federal actions between the Company and TriStar were dismissed with prejudice and without payment of damages.
	Commitments
	AT&T Transaction—The Company has an agreement with SBC Communications Inc., a predecessor entity to AT&T Inc. (“AT&T”), that currently provides for the lease or sublease of approximately 2,430 towers from AT&T with the lease commencing between December 2000 and August 2004. Substantially all of the towers are part of the Company’s securitization transaction completed in March 2013. 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. The Company 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. As of June 30, 2014, the Company has purchased four of the subleased towers upon expiration of the applicable agreement. The aggregate purchase option price for the remaining towers leased and subleased is approximately $623.5 million, 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 the Company prior to June 30, 2020, AT&T will continue to lease the reserved space at the then-current monthly fee which shall escalate in accordance with the standard master lease agreement for the remainder of AT&T’s tenancy. Thereafter, AT&T shall have the right to renew such lease for up to four successive five-year terms. For all such sites purchased by the Company subsequent to June 30, 2020, 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.
	Verizon Transaction—In December 2000, the Company entered into an agreement with ALLTEL, a predecessor entity to Verizon Wireless (“Verizon”), to acquire towers through a 15-year sublease agreement. Pursuant to the agreement, as amended, with Verizon, the Company acquired rights to 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 is approximately $72.2 million as of June 30, 2014. At Verizon’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, which would be valued at approximately $122.8 million in the aggregate based on the closing price at June 30, 2014.
	Other Contingencies—The Company is subject to income tax and other taxes in the geographic areas where it operates, and periodically receives notifications of audits, assessments or other actions by taxing authorities. The Company evaluates the circumstances of each notification based on the information available, and records a liability for any potential outcome that is probable or more likely than not unfavorable, if the liability is also reasonably estimable. On January 21, 2014, the Company received an income tax assessment in the amount of 22.6 billion Indian Rupees (approximately $369.0 million on the date of assessment), asserting tax liabilities arising out of a transfer pricing review of transactions by Essar Telecom Infrastructure Private Limited (“ETIPL”), and more specifically involving the issuance of share capital and the determination by the tax authority that an income tax obligation arose as a result of such issuance. The assessment was made with respect to transactions that took place in the tax year commencing in 2008, prior to the Company’s acquisition of ETIPL. Under the Company’s definitive acquisition agreement of ETIPL, the seller is obligated to indemnify and defend the Company with respect to any tax-related liability that may arise from activities prior to March 31, 2010. The Company believes that there is no basis upon which the tax assessment can be enforced under existing tax law and accordingly has not recorded an obligation in the consolidated financial statements. The assessment is being challenged with the appellate authorities.

Acquisitions

Acquisitions	6 Months Ended
	Jun. 30, 2014
Business Combination, Description [Abstract]	'
Acquisitions	'
	Acquisitions
	All of the acquisitions described below are accounted for as business combinations and are consistent with the Company’s strategy to expand in selected geographic areas.
	The estimates of the fair value of the assets acquired and liabilities assumed at the date of the applicable acquisition are subject to adjustment during the measurement period (up to one year from the particular acquisition date). The primary areas of the preliminary purchase price allocations that are not yet finalized relate to the fair value of certain tangible and intangible assets acquired and liabilities assumed, including contingent consideration, and residual goodwill and any related tax impact. The fair value of these net assets acquired are based on management’s estimates and assumptions, as well as other information compiled by management, including valuations that utilize customary valuation procedures and techniques. While the Company believes that such preliminary estimates provide a reasonable basis for estimating the fair value of assets acquired and liabilities assumed, it will evaluate any necessary information prior to finalization of the fair value. During the measurement period, the Company will adjust assets or liabilities if new information is obtained about facts and circumstances that existed as of the acquisition date that, if known, would have resulted in the revised estimated values of those assets or liabilities as of that date. The effect of measurement period adjustments to the estimated fair values is reflected as if the adjustments had been completed on the acquisition date. The impact of all changes that do not qualify as measurement period adjustments are included in current period earnings. If the actual results differ from the estimates and judgments used in these fair values, the amounts recorded in the condensed consolidated financial statements could be subject to a possible impairment of the intangible assets or goodwill, or require acceleration of the amortization expense of intangible assets in subsequent periods. During the six months ended June 30, 2014, the Company made certain purchase accounting measurement period adjustments related to several acquisitions and therefore retrospectively adjusted the fair value of the assets acquired and liabilities assumed in the condensed consolidated balance sheet as of December 31, 2013.
	Impact of current year acquisitions—The Company typically acquires communications sites from wireless carriers or other tower operators and subsequently integrates those sites into its existing portfolio of communications sites. The financial results of the Company’s acquisitions have been included in the Company’s condensed consolidated statements of operations for the three and six months ended June 30, 2014 from the date of respective acquisition. The date of acquisition, and by extension the point at which the Company begins to recognize the results of an acquisition may be dependent upon, among other things, the receipt of contractual consents, the commencement and extent of leasing arrangements and the timing of the transfer of title or rights to the assets, which may be accomplished in phases. For sites acquired from communications service providers, these sites may never have been operated as a business and were utilized solely by the seller as a component of their network infrastructure. An acquisition, depending on its size and nature, may or may not involve the transfer of business operations or employees.
	The estimated aggregate impact of the 2014 acquisitions on the Company’s revenues and gross margin for the six months ended June 30, 2014 is approximately $10.2 million and $7.6 million, respectively. The revenues and gross margin amounts also reflect incremental revenues from the addition of new tenants to the acquired sites subsequent to the date of acquisition. Incremental amounts of segment selling, general, administrative and development expense have not been reflected as the amounts attributable to acquisitions are not comparable.
	The Company recognizes acquisition and merger related costs in the period in which they are incurred and services are received. Acquisition and merger related costs may include finder’s fees, advisory, legal, accounting, valuation and other professional or consulting fees and general administrative costs, and are included in Other operating expenses in the condensed consolidated statements of operations. During the three and six months ended June 30, 2014, the Company recognized acquisition and merger related expenses, including the fair value adjustments to contingent consideration, of $4.8 million and $14.6 million, respectively. During the three and six months ended June 30, 2013, the Company recognized acquisition and merger related expenses, including the fair value adjustments to contingent consideration, of $3.3 million and $16.9 million, respectively. In addition, during the three and six months ended June 30, 2014, the Company recorded $3.2 million and $5.7 million, respectively, of integration costs related to recently closed acquisitions.
	2014 Acquisitions
	Richland Acquisition—On April 3, 2014, the Company, through one of its wholly-owned subsidiaries, acquired entities holding a portfolio of 60 communications sites, which at the time of acquisition were leased primarily to radio and television broadcast tenants, and four property interests in the United States from Richland for an aggregate purchase price of $385.9 million. The purchase price was satisfied with approximately $182.9 million in cash, approximately $6.5 million payable to the seller upon satisfaction of certain closing conditions and the assumption of $196.5 million of existing indebtedness. In June 2014, the Company repaid the outstanding indebtedness, paid prepayment consideration and wrote-off the unamortized premium associated with the fair value adjustment (see note 5).
	International Acquisitions—During the six months ended June 30, 2014, the Company acquired a total of 136 communications sites and related assets in Brazil, Ghana and Mexico, for an aggregate purchase price of $25.8 million (including value added tax of $0.8 million) and acquired additional net assets of approximately $0.1 million. The Company also acquired 299 communications sites in Mexico for an aggregate purchase price of $44.1 million (including value added tax of $5.6 million). The Company assumed net liabilities of approximately $3.8 million, resulting in total consideration of approximately $40.3 million, which was satisfied by the issuance of approximately $36.3 million of credits to be applied against trade accounts receivable and cash consideration of approximately $4.0 million. Each purchase price is subject to post-closing adjustments.
	Other U.S. Acquisitions—During the six months ended June 30, 2014, the Company acquired a total of 30 communications sites and equipment, as well as four property interests, in the United States for an aggregate purchase price of $33.6 million (including $0.4 million of contingent consideration). The Company also assumed net liabilities of approximately $0.4 million, resulting in total consideration of approximately $33.2 million. The aggregate purchase price is subject to post-closing adjustments.
	The following table summarizes the preliminary allocation of the aggregate purchase price paid and the amounts of assets acquired and liabilities assumed for the fiscal year 2014 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Balances are reflected in the accompanying condensed consolidated balance sheets as of June 30, 2014.
			Richland			International			Other U.S.
	Current assets		$	7,819		$	7,309		$	20
	Non-current assets		—			996			—
	Property and equipment		173,686			29,900			7,696
	Intangible assets (1):
	Customer-related intangible assets		185,000			20,409			18,928
	Network location intangible assets		1,800			10,772			3,370
	Current liabilities		(3,954		)	(1,307		)	(439		)
	Long-term obligations (2)		(201,999		)	—			—
	Other non-current liabilities		(2,922		)	(6,126		)	(74		)
	Fair value of net assets acquired		$	159,430		$	61,953		$	29,501
	Goodwill (3)		29,996			4,232			3,675
	-1	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
	-2	Long-term obligations included $196.5 million of Richland’s existing indebtedness and a fair value adjustment of $5.5 million. The fair value adjustment was based primarily on reported market values using Level 2 inputs.
	-3	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.
	2013 Acquisitions
	MIPT Acquisition
	On October 1, 2013, the Company, through its wholly owned subsidiary American Tower Investments LLC, acquired 100% of the outstanding common membership interests of MIPT, a private REIT and the parent company of GTP, an owner and operator, through its various operating subsidiaries, of approximately 4,860 communications sites in the United States and approximately 510 communications sites in Costa Rica and Panama. GTP also manages rooftops and holds property interests that it leases to communications service providers and third-party tower operators.
	The preliminary purchase price of $4.9 billion was satisfied with approximately $3.3 billion in cash, including an aggregate of approximately $2.8 billion from borrowings under the Company’s credit facilities, and the assumption of approximately $1.5 billion of MIPT’s existing indebtedness.
	The consideration consisted of the following (in thousands):
	Cash consideration (1)	$	3,330,462
	Assumption of existing indebtedness at historical cost	1,527,621
	Estimated total purchase price	$	4,858,083
	-1	Cash consideration includes $14.5 million of an additional purchase price adjustment which was paid to the sellers during the six months ended June 30, 2014 and is reflected in Accrued expenses on the consolidated balance sheet included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
	The following table summarizes the updated allocation of the aggregate purchase price paid and the amounts of assets acquired and liabilities assumed for the MIPT acquisition based upon the estimated fair value at the date of acquisition (in thousands).
			Updated Purchase Price Allocation (1)			Preliminary Purchase Price Allocation (2)
	Cash and cash equivalents		$	35,967		$	35,967
	Restricted cash		30,883			30,883
	Accounts receivable, net		10,021			10,021
	Prepaid and other current assets		35,614			22,875
	Property and equipment		920,782			996,901
	Intangible assets (3):
	Customer-related intangible assets		2,464,300			2,629,188
	Network location intangible assets		532,000			467,300
	Notes receivable and other non-current assets		63,682			4,220
	Accounts payable		(9,456		)	(9,249		)
	Accrued expenses		(36,755		)	(37,004		)
	Accrued interest		(3,253		)	(3,253		)
	Current portion of long-term obligations		(2,820		)	(2,820		)
	Unearned revenue		(35,905		)	(35,753		)
	Long-term obligations (4)		(1,573,366		)	(1,573,366		)
	Asset retirement obligations		(43,089		)	(43,089		)
	Other non-current liabilities		(8,693		)	(37,326		)
	Fair value of net assets acquired		$	2,379,912		$	2,455,495
	Goodwill (5)		950,550			874,967
	(1) Balances are reflected in the accompanying condensed consolidated balance sheets as of June 30, 2014.
	(2) Balances are reflected in the consolidated balance sheets in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
	-3	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
	-4	Long-term obligations included $1.5 billion of MIPT’s existing indebtedness and a fair value adjustment of $53.0 million. The fair value adjustment was based primarily on reported market values using Level 2 inputs.
	-5	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will not be deductible for tax purposes.
	Other 2013 Acquisitions
	Axtel Mexico Acquisition—On January 31, 2013, the Company acquired 883 communications sites from Axtel, S.A.B. de C.V. for an aggregate purchase price of $248.5 million.
NII Acquisition—On August 8, 2013, the Company entered into an agreement with NII to acquire up to 1,666 communications sites in Mexico and 2,790 communications sites in Brazil in two separate transactions.
On November 8, 2013, the Company acquired 1,473 communications sites in Mexico from NII for an initial aggregate purchase price of approximately $436.0 million (including value added tax of approximately $60.3 million) and net assets of approximately $0.9 million for total cash consideration of approximately $436.9 million. The purchase price was subsequently reduced to approximately $427.0 million (including value added tax of approximately $59.0 million) during the six months ended June 30, 2014 as a result of post-closing adjustments, while net assets acquired remained unchanged. The purchase price is subject to further post-closing adjustments. The Company’s right to purchase additional sites in Mexico expired on May 30, 2014.
On December 6, 2013, the Company acquired 1,937 communications sites in Brazil from NII for an initial aggregate purchase price of approximately $349.0 million. The purchase price was subsequently reduced to approximately $342.7 million during the six months ended June 30, 2014 as a result of post-closing adjustments. In addition, on June 26, 2014, the Company purchased an additional 103 communications sites for an aggregate purchase price of approximately $18.6 million, which are reflected above in “2014 Acquisitions”. The purchase price is subject to post-closing adjustments and the purchase of the remaining sites is subject to diligence and customary closing conditions.
Z Sites Acquisition—On November 29, 2013, the Company acquired 238 communications sites from Z-Sites Locação de Imóveis Ltda for an aggregate purchase price of approximately $122.8 million. The purchase price was subsequently increased to approximately $123.9 million during the six months ended June 30, 2014 and is subject to post-closing adjustments.
Other International Acquisitions—During the year ended December 31, 2013, the Company acquired a total of 714 additional communications sites in Brazil, Chile, Colombia, Ghana, Mexico and South Africa, for an aggregate purchase price of $89.8 million (including contingent consideration of $4.1 million and value added tax of $4.9 million).
Other U.S. Acquisitions—During the year ended December 31, 2013, the Company acquired a total of 55 additional communications sites and 23 property interests in the United States for an aggregate purchase price of $65.6 million, subject to post-closing adjustments. The purchase price included cash paid of approximately $65.2 million and net liabilities assumed of approximately $0.4 million.
The following table summarizes the updated allocation of the aggregate purchase price paid and the amounts of assets acquired and liabilities assumed for the fiscal year 2013 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Balances are reflected in the accompanying condensed consolidated balance sheets herein.
		Axtel Mexico (1)			NII Mexico (2)			NII Brazil			Z Sites			Other International			Other U.S.
Current assets		$	—		$	59,938		$	—		$	—		$	4,863		$	1,220
Non-current assets		2,626			10,738			7,201			6,436			1,991			44
Property and equipment		86,100			143,680			111,094			26,881			44,844			23,537
Intangible assets (3):
Customer-related intangible assets		119,392			132,897			143,037			62,286			20,590			29,325
Network location intangible assets		43,031			66,069			80,568			17,350			20,727			7,935
Current liabilities		—			—			—			—			—			(454		)
Other non-current liabilities		(9,377		)	(10,478		)	(13,188		)	(1,502		)	(8,168		)	(848		)
Fair value of net assets acquired		$	241,772		$	402,844		$	328,712		$	111,451		$	84,847		$	60,759
Goodwill (4)		6,751			25,056			13,978			12,493			4,970			4,403
-1	The allocation of the purchase price was finalized during the year ended December 31, 2013.
-2	Current assets includes approximately $59.0 million of value added tax.
-3	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
-4	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.
The following table summarizes the preliminary allocation, unless otherwise noted, of the aggregate purchase price paid and the amounts of assets acquired and liabilities assumed for the fiscal year 2013 acquisitions. The allocation is based upon the estimated fair value at the date of acquisition (in thousands). Balances are reflected in the consolidated balance sheets in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
		Axtel Mexico (1)			NII Mexico (2)			NII Brazil			Z Sites			Other International			Other U.S.
Current assets		$	—		$	61,183		$	—		$	—		$	4,863		$	1,220
Non-current assets		2,626			11,969			4,484			6,157			1,991			44
Property and equipment		86,100			147,364			105,784			24,832			44,844			23,803
Intangible assets (3):
Customer-related intangible assets		119,392			135,175			149,333			64,213			20,590			29,325
Network location intangible assets		43,031			63,791			93,867			17,123			20,727			7,607
Current liabilities		—			—			—			—			—			(454		)
Other non-current liabilities		(9,377		)	(10,478		)	(13,188		)	(1,502		)	(8,168		)	(786		)
Fair value of net assets acquired		$	241,772		$	409,004		$	340,280		$	110,823		$	84,847		$	60,759
Goodwill (4)		6,751			27,928			8,704			11,953			4,970			4,403
-1	The allocation of the purchase price was finalized during the year ended December 31, 2013.
-2	Current assets includes approximately $60.3 million of value added tax.
-3	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
-4	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.
Pro Forma Consolidated Results
The following table presents the unaudited pro forma financial results as if the 2013 acquisitions had occurred on January 1, 2012 and the 2014 acquisitions had occurred on January 1, 2013 (in thousands, except per share data). Management relied on various estimates and assumptions due to the fact that some of the acquisitions never operated as a business and were utilized solely by the seller as a component of their network infrastructure. As a result, historical operating results for these acquisitions are not available. The pro forma results do not include any anticipated cost synergies, costs or other effects of the planned integration of the acquisitions. Accordingly, such pro forma amounts are not necessarily indicative of the results that actually would have occurred had the acquisitions been completed on the dates indicated, nor are they indicative of the future operating results of the Company.
		Three Months Ended June 30,						Six Months Ended June 30,
		2014			2013			2014			2013
Pro forma revenues		$	1,033,541		$	941,291		$	2,031,066		$	1,879,156
Pro forma net income attributable to American Tower Corporation common stockholders		$	230,506		$	74,956		$	434,176		$	212,146
Pro forma net income per common share amounts:
Basic net income attributable to American Tower Corporation common stockholders		$	0.58		$	0.19		$	1.1		$	0.54
Diluted net income attributable to American Tower Corporation common stockholders		$	0.58		$	0.19		$	1.09		$	0.53
Other Signed Acquisitions
BR Towers Acquisition—On June 13, 2014, the Company entered into an agreement with GPCP V, a private equity fund managed by GP Investments, Ltd., FIP Multisetorial Plus, a private equity fund managed by Bradesco BBI, and other shareholders, to acquire 100% of the equity interests of BR Towers S.A., a Brazilian telecommunications real estate company that is expected to own approximately 2,530 towers and the exclusive use rights for approximately 2,110 additional towers in Brazil at closing. The purchase price of 2.18 billion Brazilian Reais (“BRL”) (approximately $990.3 million) is subject to customary adjustments. The Company deposited 130.0 million BRL (approximately $59.0 million) in escrow for this transaction, which is reflected in Prepaid and other current assets in the condensed consolidated balance sheets as of June 30, 2014.
U.S. Acquisition—In July 2014, the Company entered into an agreement to acquire 154 communications sites in the United States for approximately $132.5 million, subject to customary adjustments.
Acquisition-Related Contingent Consideration
The Company may be required to pay additional consideration under certain agreements for the acquisition of communications sites if specific conditions are met or events occur.
Colombia—Under the terms of the agreement with Colombia Movil S.A. E.S.P., the Company is required to make additional payments upon the conversion of certain barter agreements with other wireless carriers to cash paying lease agreements. Based on current estimates, the Company expects the value of potential contingent consideration payments required to be made under the agreement to be between zero and $37.6 million and estimates it to be $24.6 million using a probability weighted average of the expected outcomes at June 30, 2014. During the three and six months ended June 30, 2014, the Company recorded an increase in fair value of $0.5 million and $1.0 million, respectively, in Other operating expenses in the accompanying condensed consolidated statements of operations.
Ghana—Under the terms of its agreement, as amended, with MTN Group Limited, the Company is required to make additional payments upon the conversion of certain barter agreements with other wireless carriers to cash paying lease agreements. Based on current estimates, the Company expects the value of potential contingent consideration payments required to be made under the amended agreement to be between zero and $0.5 million and estimates it to be $0.5 million using a probability weighted average of the expected outcomes at June 30, 2014.
MIPT—In connection with the acquisition of MIPT, the Company assumed additional contingent consideration liability related to previously closed acquisitions in Costa Rica, Panama and the United States. The Company is required to make additional payments to the sellers if certain pre-designated tenant leases commence during a limited specified period of time after the applicable acquisition was completed, generally one year or less. The Company initially recorded $9.3 million of contingent consideration liability as part of the preliminary purchase price allocation upon closing of the acquisition. Based on current estimates, the Company expects the value of potential contingent consideration payments required to be made under these agreements to be between zero and $6.1 million and estimates it to be $5.5 million using a probability weighted average of the expected outcomes at June 30, 2014. During the three and six months ended June 30, 2014, the Company recorded a decrease in fair value of $1.4 million in Other operating expenses in the accompanying condensed consolidated statements of operations. During the three and six months ended June 30, 2014, the Company made payments under these agreements of $0.7 million and $1.3 million, respectively.
Other U.S.—In connection with other acquisitions in the United States, the Company is required to make additional payments if certain pre-designated tenant leases commence during a specified period of time. The Company initially recorded $0.4 million of contingent consideration liability as part of the preliminary purchase price allocation upon closing of certain acquisitions, which, based on current estimates, also represents the estimated balance at June 30, 2014 and the maximum potential liability.
For more information regarding contingent consideration, see note 7.

Business_Segments

Business Segments	6 Months Ended
	Jun. 30, 2014
Segment Reporting, Measurement Disclosures [Abstract]	'
Business Segments	'
	Business Segments
	The Company operates in three business segments, (i) domestic rental and management, (ii) international rental and management and (iii) network development services. The Company’s primary business is leasing antenna space on multi-tenant communications sites to wireless service providers, radio and television broadcast companies, wireless data and data providers, government agencies and municipalities and tenants in a number of other industries. This business is referred to as the Company’s rental and management operations and is comprised of domestic and international segments, which, as of June 30, 2014, consist of the following:
	•	Domestic: rental and management operations in the United States; and
	•	International: rental and management operations in Brazil, Chile, Colombia, Costa Rica, Germany, Ghana, India, Mexico, Panama, Peru, South Africa and Uganda.
	The Company has applied the aggregation criteria to operations within the international rental and management operating segments on a basis consistent with management’s review of information and performance evaluation.
	The Company’s network development services segment offers tower-related services in the United States, including site acquisition, zoning and permitting services and structural analysis services, which primarily support its site leasing business and the addition of new tenants and equipment on its sites. The network development services segment is a strategic business unit that offers different services from the rental and management operating segments and requires different resources, skill sets and marketing strategies.
	The accounting policies applied in compiling segment information below are similar to those described in note 1 to the Company’s Annual Report on Form 10-K for the year ended December 31, 2013. Among other factors, in evaluating financial performance in each business segment, management uses segment gross margin and segment operating profit. The Company defines segment gross margin as segment revenue less segment operating expenses excluding stock-based compensation expense recorded in costs of operations; 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 international rental and management segment gross margin and segment operating profit 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 (loss) attributable to noncontrolling interest, Income (loss) on equity method investments and Income tax provision (benefit). The categories of expenses indicated above, such as depreciation, have been excluded from segment operating performance as they are not considered in the review of information or the evaluation of results by management. There are no significant revenues resulting from transactions between the Company’s operating segments. All intercompany transactions are eliminated to reconcile segment results and assets to the condensed consolidated statements of operations and condensed consolidated balance sheets.
	Summarized financial information concerning the Company’s reportable segments for the three and six months ended June 30, 2014 and 2013 is shown in the following tables. The “Other” column (i) represents amounts excluded from specific segments, such as business development operations, stock-based compensation expense and corporate expenses included in Selling, general, administrative and development expense; Other operating expenses; Interest income; Interest expense; Loss on retirement of long-term obligations; and Other income (expense), and (ii) reconciles segment operating profit to Income from continuing operations before income taxes, as these amounts are not utilized in assessing each segment’s performance.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Three months ended June 30, 2014	Domestic		International				Services
		(in thousands)
	Segment revenues	$	659,743	$	346,018	$	1,005,761	$	25,696			$	1,031,457
	Segment operating expenses (1)	126,340		136,501		262,841		8,981				271,822
	Interest income, TV Azteca, net	—		2,662		2,662		—				2,662
	Segment gross margin	533,403		212,179		745,582		16,715				762,297
	Segment selling, general, administrative and development expense (1)	28,313		34,472		62,785		2,326				65,111
	Segment operating profit	$	505,090	$	177,707	$	682,797	$	14,389			$	697,186
	Stock-based compensation expense									$	18,835	18,835
	Other selling, general, administrative and development expense									15,006		15,006
	Depreciation, amortization and accretion									245,427		245,427
	Other expense (principally interest expense and other expenses)									174,457		174,457
	Income from continuing operations before income taxes											$	243,461
	Total assets	$	14,149,220	$	6,466,380	$	20,615,600	$	58,611	$	173,526	$	20,847,737
	-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.5 million and $18.4 million, respectively.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Three months ended June 30, 2013	Domestic		International				Services
		(in thousands)
	Segment revenues	$	521,043	$	268,156	$	789,199	$	19,631			$	808,830
	Segment operating expenses (1)	95,208		102,752		197,960		7,343				205,303
	Interest income, TV Azteca, net	—		3,586		3,586		—				3,586
	Segment gross margin	425,835		168,990		594,825		12,288				607,113
	Segment selling, general, administrative and development expense (1)	24,243		32,490		56,733		2,324				59,057
	Segment operating profit	$	401,592	$	136,500	$	538,092	$	9,964			$	548,056
	Stock-based compensation expense									$	17,055	17,055
	Other selling, general, administrative and development expense									24,097		24,097
	Depreciation, amortization and accretion									184,608		184,608
	Other expense (principally interest expense and other (expense) income)									249,630		249,630
	Income from continuing operations before income taxes											$	72,666
	Total assets	$	8,618,294	$	5,414,526	$	14,032,820	$	48,603	$	257,971	$	14,339,394
	-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.4 million and $16.6 million, respectively.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Six months ended June 30, 2014	Domestic		International				Services
		(in thousands)
	Segment revenues	$	1,295,522	$	670,359	$	1,965,881	$	49,665			$	2,015,546
	Segment operating expenses (1)	247,849		265,455		513,304		18,783				532,087
	Interest income, TV Azteca, net	—		5,257		5,257		—				5,257
	Segment gross margin	1,047,673		410,161		1,457,834		30,882				1,488,716
	Segment selling, general, administrative and development expense (1)	55,722		63,688		119,410		4,856				124,266
	Segment operating profit	$	991,951	$	346,473	$	1,338,424	$	26,026			$	1,364,450
	Stock-based compensation expense									$	43,439	43,439
	Other selling, general, administrative and development expense									41,780		41,780
	Depreciation, amortization and accretion									491,190		491,190
	Other expense (principally interest expense and other expenses)									333,618		333,618
	Income from continuing operations before income taxes											$	454,423
	-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.0 million and $42.5 million, respectively.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Six months ended June 30, 2013	Domestic		International				Services
		(in thousands)
	Segment revenues	$	1,036,719	$	529,913	$	1,566,632	$	44,926			$	1,611,558
Segment operating expenses (1)	187,041		201,968		389,009		17,622				406,631
Interest income, TV Azteca, net	—		7,129		7,129		—				7,129
Segment gross margin	849,678		335,074		1,184,752		27,304				1,212,056
Segment selling, general, administrative and development expense (1)	47,141		62,025		109,166		5,225				114,391
Segment operating profit	$	802,537	$	273,049	$	1,075,586	$	22,079			$	1,097,665
Stock-based compensation expense									$	38,097	38,097
Other selling, general, administrative and development expense									49,312		49,312
Depreciation, amortization and accretion									370,412		370,412
Other expense (principally interest expense and other (expense) income)									387,008		387,008
Income from continuing operations before income taxes											$	252,836
-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.8 million and $37.3 million, respectively.

Description_of_Business_Basis_1

Description of Business, Basis of Presentation and Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Principles of Consolidation and Basis of Presentation	'
	Principles of Consolidation and Basis of Presentation—The accompanying condensed consolidated financial statements include the accounts of the Company and those entities in which it has a controlling interest. Investments in entities that the Company does not control are accounted for using the equity or cost method, depending upon the Company’s ability to exercise significant influence over operating and financial policies. All intercompany accounts and transactions have been eliminated.
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. The significant estimates in the accompanying condensed consolidated financial statements include impairment of long-lived assets (including goodwill), asset retirement obligations, revenue recognition, rent expense, stock-based compensation, income taxes and accounting for business combinations. 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.
Functional Currency	'
	Functional Currency—The functional currency of the Company’s foreign operating subsidiaries is the respective local currency, except for Costa Rica and Panama, where the functional currency is the U.S. Dollar.  All foreign currency assets and liabilities held by the subsidiaries are translated into U.S. Dollars at the exchange rate in effect at the end of the applicable fiscal reporting period and all foreign currency revenues and expenses are translated at the average monthly exchange rates. Translation adjustments are reflected in equity as a component of Accumulated other comprehensive income (loss) (“AOCI”) in the condensed consolidated balance sheets.
	Transactional gains and losses on foreign currency transactions are reflected in Other expense in the condensed consolidated statements of operations.  However, the effect from fluctuations in foreign currency exchange rates on intercompany notes whose payment is not planned or anticipated in the foreseeable future is reflected in AOCI in the condensed consolidated balance sheets.  During the three months ended June 30, 2014, the Company recorded unrealized foreign currency losses of $53.2 million, of which $29.6 million was recorded in AOCI and $23.6 million was recorded in Other expense. During the six months ended June 30, 2014, the Company recorded unrealized foreign currency losses of $68.7 million, of which $43.1 million was recorded in AOCI and $25.6 million was recorded in Other expense.
Accounting Standards Updates	'
	Accounting Standards Updates—In April 2014, the Financial Accounting Standards Board (the “FASB”) issued additional guidance on reporting discontinued operations. Under this guidance, only disposals representing a strategic shift in operations would be presented as discontinued operations. This guidance requires expanded disclosure that provides information about the assets, liabilities, income and expenses of discontinued operations. Additionally, the guidance requires additional disclosure for a disposal of a significant part of an entity that does not qualify for discontinued operations reporting. This guidance will be effective for reporting periods beginning on or after December 15, 2014 with early adoption permitted for disposals or classifications of assets as held-for-sale that have not been reported in financial statements previously issued or available for issuance. The Company adopted this guidance during the six months ended June 30, 2014 and the adoption did not have a material effect on the Company’s financial statements.
	In May 2014, the FASB issued new revenue recognition guidance, which requires an entity to recognize revenue in an amount that reflects the consideration to which the entity expects to be entitled in exchange for the transfer of promised goods or services to customers. The standard will replace most existing revenue recognition guidance in GAAP. The amendment will become effective on January 1, 2017, and early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. Leases are not included in the scope of this standard. The Company is evaluating the impact this standard will have on its financial statements.

Prepaid_and_Other_Current_Asse1

Prepaid and Other Current Assets (Tables)	6 Months Ended
	Jun. 30, 2014
Prepaid Expense and Other Assets, Current [Abstract]	'
Prepaid expense and other current assets	'
	Prepaid and other current assets consists of the following as of (in thousands):
		30-Jun-14		December 31, 2013 (1)
	Prepaid operating ground leases	$	86,700	$	95,580
	Prepaid income tax	62,593		52,612
	Acquisition deposit in escrow	59,024		—
	Unbilled receivables	37,871		25,412
	Prepaid assets	26,693		34,243
	Value added tax and other consumption tax receivables	15,730		77,016
	Other miscellaneous current assets	54,187		56,022
	Balance	$	342,798	$	340,885
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Changes in the carrying value of goodwill	'
	The changes in the carrying value of goodwill for the Company’s business segments are as follows (in thousands):
			Rental and Management						Network				Total
									Development
			Domestic			International			Services
	Balance as of January 1, 2014 (1)		$	3,258,680		$	547,746		$	2,000			$	3,808,426
	Additions		33,671			4,232			—				37,903
	Effect of foreign currency translation		—			8,614			—				8,614
	Other (2)		—			—			(12		)		(12		)
	Balance as of June 30, 2014		$	3,292,351		$	560,592		$	1,988			$	3,854,931
	-1	Balances have been revised to reflect purchase accounting measurement period adjustments.
	-2	Other represents the fair value adjustment to goodwill associated with the Company’s third-party structural analysis business, which was considered held-for-sale at June 30, 2014.
Schedule of finite-lived intangible assets	'
	The Company’s other intangible assets subject to amortization consist of the following as of (in thousands):
					30-Jun-14											December 31, 2013 (1)
			Estimated		Gross			Accumulated				Net Book				Gross		Accumulated			Net Book
			Useful		Carrying			Amortization				Value				Carrying		Amortization			Value
			Lives		Value											Value
			(years)
	Acquired network location (2)		Up to 20		$	2,437,303		$	(869,234	)		$	1,568,069			$	2,419,708	$	(791,359	)	$	1,628,349
	Acquired customer-related intangibles		15-20		6,283,602			(1,307,289		)		4,976,313				6,026,480		(1,170,239		)	4,856,241
	Acquired licenses and other intangibles		20-Mar		6,755			(2,815		)		3,940				6,583		(2,297		)	4,286
	Economic Rights, TV Azteca		70		28,927			(14,560		)		14,367				28,783		(14,229		)	14,554
	Total				$	8,756,587		$	(2,193,898	)		$	6,562,689			$	8,481,554	$	(1,978,124	)	$	6,503,430
	Deferred financing  costs, net (3)		N/A									75,193									76,875
	Other intangible assets, net											$	6,637,882								$	6,580,305
	-1	Balances have been revised to reflect purchase accounting measurement period adjustments.
	-2	Acquired network location intangibles are amortized over the shorter of the term of the corresponding ground lease taking into consideration lease renewal options and residual value or up to 20 years, as the Company considers these intangibles to be directly related to the tower assets.
	-3	Deferred financing costs are amortized over the term of the respective debt instruments to which they relate using the effective interest method. This amortization is included in Interest expense rather than in Depreciation, amortization and accretion expense.
Expected future amortization expenses	'
	Based on current exchange rates, the Company expects to record amortization expense (excluding amortization of deferred financing costs) as follows over the remaining current year and the next five subsequent years (in millions):
	Fiscal Year
	2014 (remaining year)	$	207.4
	2015	412.5
	2016	409.8
	2017	407.5
	2018	405.4
	2019	403.3

Accrued_Expenses_Tables

Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2014
Accrued Liabilities, Current [Abstract]	'
Schedule of accrued liabilities	'
	Accrued expenses consists of the following as of (in thousands):
		30-Jun-14		December 31, 2013 (1)
	Accrued construction costs	$	72,878	$	52,446
	Accrued property and real estate taxes	65,533		54,529
	Payroll and related withholdings	35,484		50,843
	Accrued rent	34,002		28,456
	Other accrued expenses	214,717		228,801
	Balance	$	422,614	$	415,075
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2014
Summary of Derivative Instruments [Abstract]	'
Schedule of derivative financial instruments	'
	The notional amount and fair value of the interest rate swap agreements are as follows (in thousands):
		30-Jun-14					31-Dec-13
		Local		USD			Local		USD
	South Africa (ZAR)
	Notional	457,079		42,969			469,354		44,732
	Fair Value	3,773		355			939		90
	Colombia (COP)
	Notional	100,743,750		53,553			101,250,000		52,547
	Fair Value	(1,625,102	)	(864	)		(3,000,236	)	(1,557	)
	Costa Rica (USD)
	Notional	—		—			N/A		42,000
	Fair Value	—		—			N/A		(628	)
Schedule of interest rate swap agreements' impact on other comprehensive income	'
	During the three months ended June 30, 2014 and 2013, the interest rate swap agreements had the following impact on the Company’s condensed consolidated financial statements (in thousands):
	Three Months Ended June 30,	Gain(Loss) Recognized in Other Comprehensive Income - Effective Portion		Gain(Loss)		Location of Gain(Loss) Reclassified from AOCI into Income- Effective Portion		Gain(Loss) Recognized		Location of Gain(Loss) Recognized in Income -
				Reclassified from				in Income - Ineffective Portion		Ineffective Portion
				AOCI into
				Income -
				Effective Portion
	2014	$226		($670)		Interest Expense		N/A		N/A
	2013	$4,138		($704)		Interest Expense		N/A		N/A
	During the six months ended June 30, 2014 and 2013, the interest rate swap agreements had the following impact on the Company’s condensed consolidated financial statements (in thousands):
	Six Months Ended June 30,	Gain(Loss) Recognized in Other Comprehensive Income - Effective Portion		Gain(Loss)		Location of Gain(Loss) Reclassified from AOCI into Income- Effective Portion		Gain(Loss) Recognized		Location of Gain(Loss) Recognized in Income -
				Reclassified from				in Income - Ineffective Portion		Ineffective Portion
				AOCI into
				Income -
				Effective Portion
	2014	($361)		($1,639)		Interest Expense		N/A		N/A
	2013	$3,205		($1,312)		Interest Expense		N/A		N/A

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Schedule of fair value, assets and liabilities measured on 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 (in thousands):
		June 30, 2014
		Fair Value Measurements Using								Assets/Liabilities
		Level 1		Level 2				Level 3		at Fair Value
	Assets:
	Short-term investments (1)			$	15,298					$	15,298
	Interest rate swap agreements			$	355					$	355
	Liabilities:
	Acquisition-related contingent consideration							$	31,025	$	31,025
	Interest rate swap agreements			$	864					$	864
		31-Dec-13
		Fair Value Measurements Using								Assets/Liabilities
		Level 1		Level 2				Level 3		at Fair Value
	Assets:
	Short-term investments (1)			$	18,612					$	18,612
	Interest rate swap agreements			$	90					$	90
	Liabilities:
	Acquisition-related contingent consideration							$	31,890	$	31,890
	Interest rate swap agreements			$	2,185					$	2,185
	-1	Consists of highly liquid investments with original maturities in excess of three months.
Schedule of business acquisitions by acquisition, contingent consideration	'
	As of June 30, 2014, the Company estimates that the value of all potential acquisition-related contingent consideration required payments to be between zero and $44.6 million. During the three months ended June 30, 2014 and 2013, the fair value of the contingent consideration changed as follows (in thousands):
		2014				2013
	Balance as of April 1	$	31,342			$	25,201
	Additions	406				313
	Payments	(674		)		(1,033		)
	Change in fair value	(952		)		(2,007		)
	Foreign currency translation adjustment	903				(1,256		)
	Balance as of June 30	$	31,025			$	21,218
	During the six months ended June 30, 2014 and 2013, the fair value of the contingent consideration changed as follows (in thousands):
		2014				2013
	Balance as of January 1	$	31,890			$	23,711
	Additions	406				478
	Payments	(1,289		)		(4,222		)
	Change in fair value	(370		)		3,307
	Foreign currency translation adjustment	388				(2,056		)
	Balance as of June 30	$	31,025			$	21,218

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Loss (Tables)	6 Months Ended
	Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'
Schedule of accumulated other comprehensive income (loss)	'
	The changes in Accumulated other comprehensive loss for the three months ended June 30, 2014 and 2013 are as follows (in thousands):
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of April 1, 2014	$	(1,970	)	$	(2,829	)	$	(267,611	)	$	(272,410	)
	Other comprehensive income before reclassifications, net of tax	325			—			20,622			20,947
	Amounts reclassified from accumulated other comprehensive loss, net of tax	344			199			—			543
	Net current-period other comprehensive income	669			199			20,622			21,490
	Balance as of June 30, 2014	$	(1,301	)	$	(2,630	)	$	(246,989	)	$	(250,920	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of less than $0.1 million is included in income tax expense for the three months ended June 30, 2014.
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of April 1, 2013	$	(5,162	)	$	(3,628	)	$	(149,253	)	$	(158,043	)
	Other comprehensive income (loss) before reclassifications, net of tax	3,570			—			(120,394		)	(116,824		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	410			201			—			611
	Net current-period other comprehensive income (loss)	3,980			201			(120,394		)	(116,213		)
	Balance as of June 30, 2013	$	(1,182	)	$	(3,427	)	$	(269,647	)	$	(274,256	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of less than $0.1 million is included in income tax expense for the three months ended June 30, 2013.
	The changes in Accumulated other comprehensive loss for the six months ended June 30, 2014 and 2013 are as follows (in thousands):
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of January 1, 2014	$	(1,869	)	$	(3,029	)	$	(306,322	)	$	(311,220	)
	Other comprehensive (loss) income before reclassifications, net of tax	(455		)	—			59,333			58,878
	Amounts reclassified from accumulated other comprehensive loss, net of tax	1,023			399			—			1,422
	Net current-period other comprehensive income	568			399			59,333			60,300
	Balance as of June 30, 2014	$	(1,301	)	$	(2,630	)	$	(246,989	)	$	(250,920	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of $0.1 million is included in income tax expense for the six months ended June 30, 2014.
		Unrealized Losses on Cash Flow Hedges (1)			Deferred Loss on the Settlement of the Treasury Rate Lock			Foreign			Total
								Currency
								Items
	Balance as of January 1, 2013	$	(4,358	)	$	(3,827	)	$	(175,162	)	$	(183,347	)
	Other comprehensive income (loss) before reclassifications, net of tax	2,456			—			(94,485		)	(92,029		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	720			400			—			1,120
	Net current-period other comprehensive income (loss)	3,176			400			(94,485		)	(90,909		)
	Balance as of June 30, 2013	$	(1,182	)	$	(3,427	)	$	(269,647	)	$	(274,256	)
	(1) Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of $0.1 million is included in income tax expense for the six months ended June 30, 2013.

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2014
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]	'
Summary of the company's option activity	'
	The Company’s option activity for the six months ended June 30, 2014 is as follows:
		Number of
		Options
	Outstanding as of January 1, 2014	6,106,171
	Granted	1,858,633
	Exercised	(627,037	)
	Forfeited	(100,830	)
	Expired	(33,188	)
	Outstanding as of June 30, 2014	7,203,749
Assumptions used to determine the grant date fair value for options granted	'
	The fair value of each option granted during the six months ended June 30, 2014 is estimated on the date of grant using the Black-Scholes option pricing model based on the assumptions noted in the table below:
	Range of risk-free interest rate		1.46% - 1.74%
	Weighted average risk-free interest rate		1.64	%
	Expected life of option grants		4.5 years
	Range of expected volatility of underlying stock price		22.45% - 23.35%
	Weighted average expected volatility of underlying stock price		23.09	%
	Expected annual dividend yield		1.5	%
Summary of the company's restricted stock unit activity	'
	The following table summarizes the Company’s restricted stock unit activity during the six months ended June 30, 2014:
		Number of
		Units
	Outstanding as of January 1, 2014	1,840,137
	Granted	786,584
	Vested	(689,501	)
	Forfeited	(91,769	)
	Outstanding as of June 30, 2014	1,845,451
Schedule of employee stock purchase plan valuation assumptions	'
	Key assumptions used to apply the Black-Scholes pricing model for shares purchased through the ESPP during the six months ended June 30, 2014, which resulted in a fair value per share of $14.35, are as follows:
	Approximate risk-free interest rate	0.11	%
	Expected life of shares	6 months
	Expected volatility of underlying stock price over the option period	16.59	%
	Expected annual dividend yield	1.5	%

Equity_Tables

Equity (Tables)	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Schedule of dividends payable	'
	During the six months ended June 30, 2014, the Company declared the following cash distributions:
		Declaration Date	Payment Date	Record Date	Distribution per share		Aggregate Payment Amount (in millions)
	Common stock	March 6, 2014	April 25, 2014	April 10, 2014	$	0.32	$	126.6
	Common stock	May 21, 2014	July 16, 2014	June 17, 2014	$	0.34	$	134.6
	Preferred stock	May 21, 2014	15-Aug-14	1-Aug-14	$	1.3563	$	8.1

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Schedule of earnings per basic and diluted by common class	'
	The following table sets forth basic and diluted net income per common share computational data for the three and six months ended June 30, 2014 and 2013 (in thousands, except per share data):
		Three Months Ended June 30,							Six Months Ended June 30,
		2014				2013			2014			2013
	Net income attributable to American Tower Corporation stockholders	$	234,431			$	99,821		$	436,930		$	271,228
	Dividends declared on preferred stock	(4,375		)		—			(4,375		)	—
	Net income attributable to American Tower Corporation common stockholders	230,056				99,821			432,555			271,228
	Basic weighted average common shares outstanding	395,872				395,420			395,511			395,330
	Dilutive securities	3,716				4,038			3,941			4,329
	Diluted weighted average common shares outstanding	399,588				399,458			399,452			399,659
	Basic net income attributable to American Tower Corporation common stockholders per common share	$	0.58			$	0.25		$	1.09		$	0.69
	Diluted net income attributable to American Tower Corporation common stockholders per common share	$	0.58			$	0.25		$	1.08		$	0.68
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	'
	The following shares were not included in the computation of diluted earnings per share because the effect would be anti-dilutive (in thousands, on a weighted average basis):
		Three Months Ended June 30,						Six Months Ended June 30,
		2014			2013			2014		2013
	Restricted stock awards	3			—			1		—
	Stock options	2,497			1,229			2,342		860
	Preferred stock (1)	3,733			—			1,877		—
	(1)     Issued on May 12, 2014.

Acquisitions_Tables

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2014
Business Combination, Description [Abstract]	'
Schedule of recognized identified assets acquired and liabilities assumed	'
	Balances are reflected in the consolidated balance sheets in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
			Axtel Mexico (1)			NII Mexico (2)			NII Brazil			Z Sites			Other International			Other U.S.
	Current assets		$	—		$	61,183		$	—		$	—		$	4,863		$	1,220
	Non-current assets		2,626			11,969			4,484			6,157			1,991			44
	Property and equipment		86,100			147,364			105,784			24,832			44,844			23,803
	Intangible assets (3):
	Customer-related intangible assets		119,392			135,175			149,333			64,213			20,590			29,325
	Network location intangible assets		43,031			63,791			93,867			17,123			20,727			7,607
	Current liabilities		—			—			—			—			—			(454		)
	Other non-current liabilities		(9,377		)	(10,478		)	(13,188		)	(1,502		)	(8,168		)	(786		)
	Fair value of net assets acquired		$	241,772		$	409,004		$	340,280		$	110,823		$	84,847		$	60,759
	Goodwill (4)		6,751			27,928			8,704			11,953			4,970			4,403
	-1	The allocation of the purchase price was finalized during the year ended December 31, 2013.
	-2	Current assets includes approximately $60.3 million of value added tax.
	-3	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
	-4	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.
	The following table summarizes the updated allocation of the aggregate purchase price paid and the amounts of assets acquired and liabilities assumed for the fiscal year 2013 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Balances are reflected in the accompanying condensed consolidated balance sheets herein.
			Axtel Mexico (1)			NII Mexico (2)			NII Brazil			Z Sites			Other International			Other U.S.
	Current assets		$	—		$	59,938		$	—		$	—		$	4,863		$	1,220
	Non-current assets		2,626			10,738			7,201			6,436			1,991			44
	Property and equipment		86,100			143,680			111,094			26,881			44,844			23,537
	Intangible assets (3):
	Customer-related intangible assets		119,392			132,897			143,037			62,286			20,590			29,325
	Network location intangible assets		43,031			66,069			80,568			17,350			20,727			7,935
	Current liabilities		—			—			—			—			—			(454		)
	Other non-current liabilities		(9,377		)	(10,478		)	(13,188		)	(1,502		)	(8,168		)	(848		)
	Fair value of net assets acquired		$	241,772		$	402,844		$	328,712		$	111,451		$	84,847		$	60,759
	Goodwill (4)		6,751			25,056			13,978			12,493			4,970			4,403
	-1	The allocation of the purchase price was finalized during the year ended December 31, 2013.
	-2	Current assets includes approximately $59.0 million of value added tax.
	-3	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
	-4	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.
	The following table summarizes the updated allocation of the aggregate purchase price paid and the amounts of assets acquired and liabilities assumed for the MIPT acquisition based upon the estimated fair value at the date of acquisition (in thousands).
			Updated Purchase Price Allocation (1)			Preliminary Purchase Price Allocation (2)
	Cash and cash equivalents		$	35,967		$	35,967
	Restricted cash		30,883			30,883
	Accounts receivable, net		10,021			10,021
	Prepaid and other current assets		35,614			22,875
	Property and equipment		920,782			996,901
	Intangible assets (3):
	Customer-related intangible assets		2,464,300			2,629,188
	Network location intangible assets		532,000			467,300
	Notes receivable and other non-current assets		63,682			4,220
	Accounts payable		(9,456		)	(9,249		)
	Accrued expenses		(36,755		)	(37,004		)
	Accrued interest		(3,253		)	(3,253		)
	Current portion of long-term obligations		(2,820		)	(2,820		)
	Unearned revenue		(35,905		)	(35,753		)
	Long-term obligations (4)		(1,573,366		)	(1,573,366		)
	Asset retirement obligations		(43,089		)	(43,089		)
	Other non-current liabilities		(8,693		)	(37,326		)
	Fair value of net assets acquired		$	2,379,912		$	2,455,495
	Goodwill (5)		950,550			874,967
	(1) Balances are reflected in the accompanying condensed consolidated balance sheets as of June 30, 2014.
	(2) Balances are reflected in the consolidated balance sheets in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
	-3	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
	-4	Long-term obligations included $1.5 billion of MIPT’s existing indebtedness and a fair value adjustment of $53.0 million. The fair value adjustment was based primarily on reported market values using Level 2 inputs.
	-5	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will not be deductible for tax purposes.
	Balances are reflected in the accompanying condensed consolidated balance sheets as of June 30, 2014.
			Richland			International			Other U.S.
	Current assets		$	7,819		$	7,309		$	20
	Non-current assets		—			996			—
	Property and equipment		173,686			29,900			7,696
Intangible assets (1):
Customer-related intangible assets		185,000			20,409			18,928
Network location intangible assets		1,800			10,772			3,370
Current liabilities		(3,954		)	(1,307		)	(439		)
Long-term obligations (2)		(201,999		)	—			—
Other non-current liabilities		(2,922		)	(6,126		)	(74		)
Fair value of net assets acquired		$	159,430		$	61,953		$	29,501
Goodwill (3)		29,996			4,232			3,675
-1	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
-2	Long-term obligations included $196.5 million of Richland’s existing indebtedness and a fair value adjustment of $5.5 million. The fair value adjustment was based primarily on reported market values using Level 2 inputs.
-3	Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.
Fair value of consideration transferred	'
	The consideration consisted of the following (in thousands):
	Cash consideration (1)	$	3,330,462
	Assumption of existing indebtedness at historical cost	1,527,621
	Estimated total purchase price	$	4,858,083
	-1	Cash consideration includes $14.5 million of an additional purchase price adjustment which was paid to the sellers during the six months ended June 30, 2014 and is reflected in Accrued expenses on the consolidated balance sheet included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
Business acquisition, pro forma information	'
	Accordingly, such pro forma amounts are not necessarily indicative of the results that actually would have occurred had the acquisitions been completed on the dates indicated, nor are they indicative of the future operating results of the Company.
			Three Months Ended June 30,						Six Months Ended June 30,
			2014			2013			2014			2013
	Pro forma revenues		$	1,033,541		$	941,291		$	2,031,066		$	1,879,156
	Pro forma net income attributable to American Tower Corporation common stockholders		$	230,506		$	74,956		$	434,176		$	212,146
	Pro forma net income per common share amounts:
	Basic net income attributable to American Tower Corporation common stockholders		$	0.58		$	0.19		$	1.1		$	0.54
	Diluted net income attributable to American Tower Corporation common stockholders		$	0.58		$	0.19		$	1.09		$	0.53

Business_Segments_Tables

Business Segments (Tables)	6 Months Ended
	Jun. 30, 2014
Segment Reporting, Measurement Disclosures [Abstract]	'
Summarized financial information concerning the company's reportable segments	'
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Three months ended June 30, 2014	Domestic		International				Services
		(in thousands)
	Segment revenues	$	659,743	$	346,018	$	1,005,761	$	25,696			$	1,031,457
	Segment operating expenses (1)	126,340		136,501		262,841		8,981				271,822
	Interest income, TV Azteca, net	—		2,662		2,662		—				2,662
	Segment gross margin	533,403		212,179		745,582		16,715				762,297
	Segment selling, general, administrative and development expense (1)	28,313		34,472		62,785		2,326				65,111
	Segment operating profit	$	505,090	$	177,707	$	682,797	$	14,389			$	697,186
	Stock-based compensation expense									$	18,835	18,835
	Other selling, general, administrative and development expense									15,006		15,006
	Depreciation, amortization and accretion									245,427		245,427
	Other expense (principally interest expense and other expenses)									174,457		174,457
	Income from continuing operations before income taxes											$	243,461
	Total assets	$	14,149,220	$	6,466,380	$	20,615,600	$	58,611	$	173,526	$	20,847,737
	-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.5 million and $18.4 million, respectively.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Six months ended June 30, 2013	Domestic		International				Services
		(in thousands)
	Segment revenues	$	1,036,719	$	529,913	$	1,566,632	$	44,926			$	1,611,558
	Segment operating expenses (1)	187,041		201,968		389,009		17,622				406,631
	Interest income, TV Azteca, net	—		7,129		7,129		—				7,129
	Segment gross margin	849,678		335,074		1,184,752		27,304				1,212,056
	Segment selling, general, administrative and development expense (1)	47,141		62,025		109,166		5,225				114,391
	Segment operating profit	$	802,537	$	273,049	$	1,075,586	$	22,079			$	1,097,665
	Stock-based compensation expense									$	38,097	38,097
	Other selling, general, administrative and development expense									49,312		49,312
	Depreciation, amortization and accretion									370,412		370,412
	Other expense (principally interest expense and other (expense) income)									387,008		387,008
	Income from continuing operations before income taxes											$	252,836
	-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.8 million and $37.3 million, respectively.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Three months ended June 30, 2013	Domestic		International				Services
		(in thousands)
	Segment revenues	$	521,043	$	268,156	$	789,199	$	19,631			$	808,830
	Segment operating expenses (1)	95,208		102,752		197,960		7,343				205,303
	Interest income, TV Azteca, net	—		3,586		3,586		—				3,586
	Segment gross margin	425,835		168,990		594,825		12,288				607,113
	Segment selling, general, administrative and development expense (1)	24,243		32,490		56,733		2,324				59,057
	Segment operating profit	$	401,592	$	136,500	$	538,092	$	9,964			$	548,056
	Stock-based compensation expense									$	17,055	17,055
	Other selling, general, administrative and development expense									24,097		24,097
	Depreciation, amortization and accretion									184,608		184,608
	Other expense (principally interest expense and other (expense) income)									249,630		249,630
	Income from continuing operations before income taxes											$	72,666
	Total assets	$	8,618,294	$	5,414,526	$	14,032,820	$	48,603	$	257,971	$	14,339,394
	-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.4 million and $16.6 million, respectively.
		Rental and Management				Total Rental and		Network		Other		Total
						Management		Development
	Six months ended June 30, 2014	Domestic		International				Services
		(in thousands)
	Segment revenues	$	1,295,522	$	670,359	$	1,965,881	$	49,665			$	2,015,546
	Segment operating expenses (1)	247,849		265,455		513,304		18,783				532,087
	Interest income, TV Azteca, net	—		5,257		5,257		—				5,257
	Segment gross margin	1,047,673		410,161		1,457,834		30,882				1,488,716
	Segment selling, general, administrative and development expense (1)	55,722		63,688		119,410		4,856				124,266
	Segment operating profit	$	991,951	$	346,473	$	1,338,424	$	26,026			$	1,364,450
	Stock-based compensation expense									$	43,439	43,439
	Other selling, general, administrative and development expense									41,780		41,780
	Depreciation, amortization and accretion									491,190		491,190
Other expense (principally interest expense and other expenses)									333,618		333,618
Income from continuing operations before income taxes											$	454,423
-1	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.0 million and $42.5 million, respectively.

Description_of_Business_Basis_2

Description of Business, Basis of Presentation and Accounting Policies (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Gain (Loss) on Investments [Line Items]	'	'	'	'
Foreign currency transaction gain (loss), in AOCI and Income Statement	($53,200,000)	'	($68,700,000)	'
Unrealized foreign currency losses	-23,553,000	-142,909,000	-25,558,000	-120,766,000
Reclassified to AOCI [Member]	'	'	'	'
Gain (Loss) on Investments [Line Items]	'	'	'	'
Foreign currency transaction gain (loss), reclassified as AOCI	$29,600,000	'	$43,100,000	'

Prepaid_and_Other_Current_Asse2

Prepaid and Other Current Assets (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Prepaid Expense and Other Assets, Current [Abstract]	'	'
Prepaid operating ground leases	$86,700	$95,580	[1]
Prepaid income tax	62,593	52,612	[1]
Acquisition deposit in escrow	59,024	0	[1]
Unbilled receivables	37,871	25,412	[1]
Prepaid assets	26,693	34,243	[1]
Value added tax and other consumption tax receivables	15,730	77,016	[1]
Other miscellaneous current assets	54,187	56,022	[1]
Balance	$342,798	$340,885	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'	'	'	'
Weighted average amortization period of intangible assets, years	'	'	'16 years	'
Amortization of intangible assets	$101.60	$61.10	$204.20	$120.30
Goodwill and Intangible Asset Impairment	$4.10	'	'	'

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Rollforward) (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014
Goodwill [Roll Forward]	'
Balance as of January 1, 2014	$3,808,426	[1]
Additions	37,903
Effect of foreign currency translation	8,614
Other	-12	[2]
Balance as of June 30, 2014	3,854,931
Rental And Management [Member] | Domestic [Member]	'
Goodwill [Roll Forward]	'
Balance as of January 1, 2014	3,258,680	[1]
Additions	33,671
Effect of foreign currency translation	0
Other	0	[2]
Balance as of June 30, 2014	3,292,351
Rental And Management [Member] | International [Member]	'
Goodwill [Roll Forward]	'
Balance as of January 1, 2014	547,746	[1]
Additions	4,232
Effect of foreign currency translation	8,614
Other	0	[2]
Balance as of June 30, 2014	560,592
Network Development Services [Member]	'
Goodwill [Roll Forward]	'
Balance as of January 1, 2014	2,000	[1]
Additions	0
Effect of foreign currency translation	0
Other	-12	[2]
Balance as of June 30, 2014	$1,988
[1]	Balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Other represents the fair value adjustment to goodwill associated with the Company’s third-party structural analysis business, which was considered held-for-sale at June 30, 2014.

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Changes in the Carrying Value of Goodwill) (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]	'		'
Gross Carrying Value	$8,756,587		$8,481,554	[1]
Accumulated Amortization	-2,193,898		-1,978,124	[1]
Net Book Value	6,562,689		6,503,430	[1]
Deferred financing costs, net	75,193	[2]	76,875	[1],[2]
Other intangible assets, net	6,637,882		6,580,305	[1]
Acquired Network Location [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Gross Carrying Value	2,437,303	[3]	2,419,708	[1],[3]
Accumulated Amortization	-869,234	[3]	-791,359	[1],[3]
Net Book Value	1,568,069	[3]	1,628,349	[1],[3]
Acquired Network Location [Member] | Maximum [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Estimated useful lives	'20 years		'
Acquired Customer Relationships [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Gross Carrying Value	6,283,602		6,026,480	[1]
Accumulated Amortization	-1,307,289		-1,170,239	[1]
Net Book Value	4,976,313		4,856,241	[1]
Acquired Customer Relationships [Member] | Minimum [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Estimated useful lives	'15 years		'
Acquired Customer Relationships [Member] | Maximum [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Estimated useful lives	'20 years		'
Acquired Licenses And Other Intangibles [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Gross Carrying Value	6,755		6,583	[1]
Accumulated Amortization	-2,815		-2,297	[1]
Net Book Value	3,940		4,286	[1]
Acquired Licenses And Other Intangibles [Member] | Minimum [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Estimated useful lives	'3 years		'
Acquired Licenses And Other Intangibles [Member] | Maximum [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Estimated useful lives	'20 years		'
Economic Rights, TV Azteca [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Gross Carrying Value	28,927		28,783	[1]
Accumulated Amortization	-14,560		-14,229	[1]
Net Book Value	$14,367		$14,554	[1]
Estimated useful lives	'70 years		'
[1]	Balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Deferred financing costs are amortized over the term of the respective debt instruments to which they relate using the effective interest method. This amortization is included in Interest expense rather than in Depreciation, amortization and accretion expense.
[3]	Acquired network location intangibles are amortized over the shorter of the term of the corresponding ground lease taking into consideration lease renewal options and residual value or up to 20 years, as the Company considers these intangibles to be directly related to the tower assets.

Goodwill_and_Other_Intangible_5

Goodwill and Other Intangible Assets (Expected Future Amortization Expenses) (Details) (USD $)	Jun. 30, 2014
In Millions, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]	'
2014 (remaining year)	$207.40
2015	412.5
2016	409.8
2017	407.5
2018	405.4
2019	$403.30

Accrued_Expenses_Details

Accrued Expenses (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accrued Liabilities, Current [Abstract]	'	'
Accrued construction costs	$72,878	$52,446	[1]
Accrued property and real estate taxes	65,533	54,529	[1]
Payroll and related withholdings	35,484	50,843	[1]
Accrued rent	34,002	28,456	[1]
Other accrued expenses	214,717	228,801	[1]
Balance	$422,614	$415,075	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Longterm_Obligations_Narrative

Long-term Obligations (Narrative) (Details)

6 Months Ended

6 Months Ended

6 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

1 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

6 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Oct. 02, 2013

Oct. 02, 2013

Jun. 30, 2014

Sep. 20, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jan. 21, 2014

Jun. 30, 2014

Jul. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jan. 10, 2014

Jun. 30, 2014

Jun. 30, 2014

Oct. 29, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

USD ($)

USD ($)

GTP Notes [Member]

GTP Notes [Member]

Four Point Six Two Five Percent Senior Notes [Member]

Three Point Four Zero and Five Point Zero Percent Senior Notes [Member] [Member]

Colombian Bridge Loan [Member]

Colombian Bridge Loan [Member]

Secured Debt [Member]

Secured Debt [Member]

Secured Debt [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Revolving Credit Facility [Member]

USD ($)

Secured Debt [Member]

Senior Notes [Member]

Short-term Debt [Member]

Short-term Debt [Member]

Richland Notes [Member]

GTP Notes [Member]

Costa Rica Loan [Member]

Short Term Credit Facility [Member]

Short Term Credit Facility [Member]

Short Term Credit Facility [Member]

Credit Facility 2012 [Member]

Credit Facility 2012 [Member]

Credit Facility 2013 [Member]

Credit Facility 2013 [Member]

Credit Facility 2013 [Member]

Credit Facility 2013 [Member]

Mexican loan [Member]

Mexican loan [Member]

Mexican loan [Member]

Mexican loan [Member]

Reopened Three Point Four Zero Percent Senior Notes [Member]

Three Point Four Zero Percent Senior Notes [Member]

Reopened Five Point Zero Percent [Member]

Five Point Zero Percent Senior Notes [Member]

Three Point Four Zero and Five Point Zero Percent Senior Notes [Member] [Member]

Three Point Four Zero and Five Point Zero Percent Senior Notes [Member] [Member]

Term Loan 2013 [Member]

Term Loan 2013 [Member]

Term Loan 2013 [Member]

Mexican loan [Member]

Colombian Loan [Member]

Credit Facility 2012 [Member]

USD ($)

USD ($)

USD ($)

COP

USD ($)

USD ($)

USD ($)

USD ($)

LIBOR Based Borrowings [Member]

USD ($)

LIBOR Based Borrowings [Member]

USD ($)

USD ($)

Subsequent Event [Member]

LIBOR Based Borrowings [Member]

USD ($)

MXN

USD ($)

MXN

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

LIBOR Based Borrowings [Member]

USD ($)

USD ($)

USD ($)

Loan

Loan

Series

renewal_periods

USD ($)

Class

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt

'

'

'

'

'

'

'

'

$196,500,000

$1,490,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$1,500,000,000

'

'

'

'

Number of series of secured debt

'

'

'

'

'

'

'

'

'

6

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of classes of secured debt

'

'

'

'

'

'

'

'

'

11

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Remaining availability under debt instrument

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

300,000,000

'

300,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Repayment of indebtedness

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

80,400,000

'

'

1,100,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Extinguishment of Debt, Gain (Loss), Net of Tax

-1,269,000

-35,288,000

'

'

'

'

'

'

-1,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from the issuance of debt

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

763,800,000

'

'

'

'

'

3,000,000

'

Stated percentage interest rate

'

'

'

'

4.63%

'

7.86%

7.86%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3.40%

'

5.00%

'

'

'

'

'

'

'

'

Debt Instrument, Redemption Price, Percentage

'

'

'

'

'

100.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Repayments of Lines of Credit

'

'

'

'

'

'

'

'

'

'

'

'

'

'

88,000,000

'

710,000,000

1,400,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt, gross

'

'

'

'

'

'

'

'

'

'

32,600,000

'

'

'

'

'

'

'

'

'

'

3,900,000,000

'

3,900,000,000

250,000,000

1,000,000,000

500,000,000

1,000,000,000

'

'

'

'

'

298,600,000

35,100,000

'

Debt Instrument, Unamortized Premium

'

'

3,400,000

'

'

'

'

'

5,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of credit facility, maximum borrowing capacity

'

'

'

'

'

'

'

'

'

'

'

'

1,000,000,000

'

1,000,000,000

'

'

2,000,000,000

'

'

'

5,200,000,000

'

5,200,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Repurchase price as percentage of principal

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

101.00%

'

'

'

'

'

'

Maximum adjusted EBITDA (in times)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3.5

'

'

'

'

'

'

Credit facility, outstanding

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

783,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0

Letters of credit outstanding

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,500,000

'

'

3,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Borrowings under credit facilities

360,000,000

249,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

360,000,000

140,000,000

'

'

4,900,000,000

374,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Basis spread on variable rate

'

'

'

'

'

'

'

'

'

'

'

'

'

1.25%

'

1.63%

'

'

'

1.25%

'

'

'

'

'

'

'

'

'

'

'

'

1.25%

'

'

'

Commitment fee percentage

'

'

'

'

'

'

'

'

'

'

'

0.15%

'

'

0.23%

'

'

0.15%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of credit facility, capacity available for specific purposes

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

750,000,000

'

'

'

'

'

'

'

'

'

'

'

'

500,000,000

'

'

'

'

'

Number of annual renewal periods

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of bridge loans

'

'

'

'

'

'

6

6

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Short term debt outstanding

'

'

'

250,000,000

600,000,000

'

57,400,000

108,000,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Unamortized Discount

'

'

'

'

$100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Narrative) (Details) (USD $)	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified		South African Facility [Member]	Colombian Long Term Credit Facility [Member]	Costa Rica Loan [Member]
		interest_rate_swap		interest_rate_swap
Derivative [Line Items]	'	'	'	'
Number of interest rate swap agreements	'	15	'	3
Derivative, lower fixed interest rate range	'	6.09%	'	'
Derivative, higher fixed interest rate range	'	7.83%	'	'
Derivative, fixed interest rate	'	'	5.78%	'
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net	$0.70	'	'	'

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Schedule of Interest Rate Swap Agreements) (Details)	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2013	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013
In Thousands, unless otherwise specified	USD ($)	USD ($)	South African Facility [Member]	South African Facility [Member]	South African Facility [Member]	South African Facility [Member]	Colombian Long Term Credit Facility [Member]	Colombian Long Term Credit Facility [Member]	Colombian Long Term Credit Facility [Member]	Colombian Long Term Credit Facility [Member]	Costa Rica Loan [Member]
			USD ($)	ZAR	USD ($)	ZAR	USD ($)	COP	USD ($)	COP	USD ($)
Derivative [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Notional	'	'	$42,969	457,079	$44,732	469,354	$53,553	100,743,750	$52,547	101,250,000	$42,000
Fair Value- Asset	355	90	355	3,773	90	939	'	'	'	'	'
Fair Value- Liability	($864)	($2,185)	'	'	'	'	($864)	-1,625,102	($1,557)	-3,000,236	($628)

Derivative_Financial_Instrumen4

Derivative Financial Instruments (Schedule of Interest Rate Swap Agreements Impact on Other Comprehensive Income) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Summary of Derivative Instruments [Abstract]	'	'	'	'
Gain(Loss) Recognized in Other Comprehensive Income - Effective Portion	$226	$4,138	($361)	$3,205
Gain(Loss) Reclassified from AOCI into Income - Effective Portion	($670)	($704)	($1,639)	($1,312)

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Business combination, contingent consideration arrangements, range of outcomes, value, low	$0	'	$0	'	'
Business combination, contingent consideration arrangements, range of outcomes, value, high	44,600,000	'	44,600,000	'	'
Asset Impairment Charges	0	0	0	100,000	'
Goodwill and Intangible Asset Impairment	4,100,000	'	'	'	'
Carrying value of long-term obligations, including current portion	14,000,000,000	'	14,000,000,000	'	14,500,000,000
Fair value of long-term obligations, including current portion	14,500,000,000	'	14,500,000,000	'	14,700,000,000
Fair Value, Inputs, Level 1 [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Fair value of long-term obligations, including current portion	9,200,000,000	'	9,200,000,000	'	8,600,000,000
Fair Value, Inputs, Level 2 [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Fair value of long-term obligations, including current portion	5,300,000,000	'	5,300,000,000	'	6,100,000,000
Portion of Engineering Business [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Assets Held-for-sale, at Carrying Value	2,400,000	'	2,400,000	'	'
Goodwill and Intangible Asset Impairment	4,127,000	'	4,100,000	'	'
PANAMA	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Assets Held-for-sale, at Carrying Value	15,100,000	'	15,100,000	'	'
PANAMA | Property, Plant and Equipment [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Assets Held-for-sale, at Carrying Value	8,000,000	'	8,000,000	'	'
PANAMA | Other Intangible Assets [Member]	'	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'
Assets Held-for-sale, at Carrying Value	$5,600,000	'	$5,600,000	'	'

Fair_Value_Measurement_Assets_

Fair Value Measurement (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $)	Jun. 30, 2014		Mar. 31, 2014	Dec. 31, 2013		Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'		'	'	'
Short-term investments	$15,298		'	$18,612	[1]	'	'	'
Interest rate swap agreements	355		'	90		'	'	'
Acquisition-related contingent consideration	31,025		31,342	31,890		21,218	25,201	23,711
Interest rate swap agreement- Liability	864		'	2,185		'	'	'
Fair Value, Inputs, Level 2 [Member]	'		'	'		'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'		'	'	'
Short-term investments	15,298	[1]	'	18,612	[1]	'	'	'
Interest rate swap agreements	'		'	90		'	'	'
Interest rate swap agreement- Liability	864		'	2,185		'	'	'
Fair Value, Inputs, Level 3 [Member]	'		'	'		'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'		'	'	'
Acquisition-related contingent consideration	$31,025		'	$31,890		'	'	'
[1]	Consists of highly liquid investments with original maturities in excess of three months.

Fair_Value_Measurement_Conting

Fair Value Measurement (Contingent Consideration Change) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Balance	$31,342	$25,201	$31,890	$23,711
Additions	406	313	406	478
Payments	-674	-1,033	-1,289	-4,222
Change in fair value	-952	-2,007	-370	3,307
Foreign currency translation adjustment	903	-1,256	388	-2,056
Balance	$31,025	$21,218	$31,025	$21,218

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Loss (Details) (USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Balance at beginning of period	($272,410)		($158,043)		($311,220)		($183,347)
Other comprehensive income before reclassifications, net of tax	20,947		-116,824		58,878		-92,029
Amounts reclassified from accumulated other comprehensive loss, net of tax	543		611		1,422		1,120
Net current-period other comprehensive income	21,490		-116,213		60,300		-90,909
Balance at end of period	-250,920		-274,256		-250,920		-274,256
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	41		59		96		118
Unrealized Losses on Cash Flow Hedges [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Balance at beginning of period	-1,970	[1]	-5,162	[2]	-1,869	[3]	-4,358	[4]
Other comprehensive income before reclassifications, net of tax	325	[1]	3,570	[2]	-455	[3]	2,456	[4]
Amounts reclassified from accumulated other comprehensive loss, net of tax	344	[1]	410	[2]	1,023	[3]	720	[4]
Net current-period other comprehensive income	669	[1]	3,980	[2]	568	[3]	3,176	[4]
Balance at end of period	-1,301	[1],[3]	-1,182	[2],[4]	-1,301	[1],[3]	-1,182	[2],[4]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	100		100		100		100
Treasury Lock [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Balance at beginning of period	-2,829		-3,628		-3,029		-3,827
Other comprehensive income before reclassifications, net of tax	0		0		0		0
Amounts reclassified from accumulated other comprehensive loss, net of tax	199		201		399		400
Net current-period other comprehensive income	199		201		399		400
Balance at end of period	-2,630		-3,427		-2,630		-3,427
Foreign Currency Items [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Balance at beginning of period	-267,611		-149,253		-306,322		-175,162
Other comprehensive income before reclassifications, net of tax	20,622		-120,394		59,333		-94,485
Amounts reclassified from accumulated other comprehensive loss, net of tax	0		0		0		0
Net current-period other comprehensive income	20,622		-120,394		59,333		-94,485
Balance at end of period	($246,989)		($269,647)		($246,989)		($269,647)
[1]	Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of less than $0.1 million is included in income tax expense for the three months ended June 30, 2014.
[2]	Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of less than $0.1 million is included in income tax expense for the three months ended June 30, 2013.
[3]	Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of $0.1 million is included in income tax expense for the six months ended June 30, 2014.
[4]	Losses on cash flow hedges have been reclassified into Interest expense in the accompanying condensed consolidated statements of operations. The tax effect of $0.1 million is included in income tax expense for the six months ended June 30, 2013.

Income_Taxes_Narrative_Details

Income Taxes (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Income Tax Expense (Benefit), Continuing Operations [Abstract]	'	'	'	'	'
Unrecognized tax benefits that would impact effective tax rate	$37,700,000	'	$37,700,000	'	$31,100,000
Impact of change in unrecognized tax benefit, lower	0	'	0	'	'
Impact of change in unrecognized tax benefits, upper	14,600,000	'	14,600,000	'	'
Penalties and tax-related interest expense during period	1,900,000	1,300,000	3,200,000	2,600,000	'
Unrecognized tax benefits, income tax penalties and interest accrued	$34,800,000	'	$34,800,000	'	$30,900,000

StockBased_Compensation_Narrat

Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Stock-based compensation expense	$18,835,000	$17,055,000	$43,439,000	$38,097,000
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost	'	1,100,000	'	1,100,000
Capitalized stock-based compensation expense	400,000	400,000	800,000	800,000
Accelerated recognition of stock-based compensation expense related to awards granted to retirement eligible employees, additional expense recognized	1,200,000	600,000	9,700,000	7,300,000
Employee Stock Option [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Weighted average grant date fair value (in dollars per share)	'	'	$14.84	'
Total unrecognized compensation expense	45,200,000	'	45,200,000	'
Total compensation cost not yet recognized, period for recognition	'	'	'2 years	'
Restricted stock awards [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Total unrecognized compensation expense	102,700,000	'	102,700,000	'
Total compensation cost not yet recognized, period for recognition	'	'	'2 years	'
Employee Stock [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Employee Stock Purchase Plan Employee Discount	15.00%	'	15.00%	'
Stock Issued During Period, Shares, Employee Stock Purchase Plans	'	'	44,000	'
Purchase Shares Fair Value Price Per Share ESPP	$14.35	'	$14.35	'
2007 Plan [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Vesting period	'	'	'4 years	'
Expiration period	'	'	'10 years	'
Number of shares issuable under stock incentive plan	14,200,000	'	14,200,000	'

StockBased_Compensation_Summar

Stock-Based Compensation (Summary of the Company's Option Activity) (Details)	6 Months Ended
	Jun. 30, 2014
Options Activity, Outstanding [Roll Forward]	'
Outstanding	6,106,171
Granted	1,858,633
Exercised	-627,037
Forfeited	-100,830
Expired	-33,188
Outstanding	7,203,749

StockBased_Compensation_Assump

Stock-Based Compensation (Assumptions Used to Determine the Grant Date Fair Value for Options Granted) (Details)	6 Months Ended
	Jun. 30, 2014
Employee Stock Purchase Plan [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Approximate risk-free interest rate	0.11%
Expected life of option grants	'6 months
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	16.59%
Expected annual dividend yield	1.50%
Employee Stock Option [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Minimum range of risk-free interest rate	1.46%
Maximum range of risk-free interest rate	1.74%
Approximate risk-free interest rate	1.64%
Expected life of option grants	'4 years 4 months 52 days
Minimum range of expected volatility of underlying stock price	22.45%
Maximum range of expected volatility of underlying stock price	23.35%
Expected volatility of underlying stock price over the option period	23.09%
Expected annual dividend yield	1.50%

StockBased_Compensation_Summar1

Stock-Based Compensation (Summary of the Company's Restricted Stock Unit Activity) (Details) (Restricted Stock Units [Member])	6 Months Ended
	Jun. 30, 2014
Restricted Stock Units [Member]	'
Restricted Stock Unit Activity, Outstanding [Roll Forward]	'
Outstanding	1,840,137
Granted	786,584
Vested	-689,501
Forfeited	-91,769
Outstanding	1,845,451

StockBased_Compensation_Schedu

Stock-Based Compensation (Schedule of Employee Stock Purchase Plan Valuation Assumptions) (Details) (Employee Stock Purchase Plan [Member])	6 Months Ended
	Jun. 30, 2014
Employee Stock Purchase Plan [Member]	'
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]	'
Approximate risk-free interest rate	0.11%
Expected life of shares	'6 months
Expected volatility of underlying stock price over the option period	16.59%
Expected annual dividend yield	1.50%

Equity_Narrative_Details

Equity (Narrative) (Details) (USD $)	6 Months Ended			1 Months Ended	6 Months Ended			6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Mar. 31, 2011	Jun. 30, 2014	Jun. 30, 2014	12-May-14	Jun. 30, 2014	Jun. 30, 2014
				Common Stock	Treasury Stock	Series A Preferred Stock [Member]	Series A Preferred Stock [Member]	Minimum [Member]	Maximum [Member]
								Series A Preferred Stock [Member]	Series A Preferred Stock [Member]
Class of Stock [Line Items]	'	'	'	'	'	'	'	'	'
Preferred Stock, Dividend Rate, Percentage	'	'	'	'	'	5.25%	'	'	'
Preferred stock, shares issued	6,000,000	'	0	'	'	'	6,000,000	'	'
Preferred Stock, Par or Stated Value Per Share	$0.01	'	$0.01	'	'	$0.01	'	'	'
Issuance of preferred stock	$583,326,000	$0	'	'	'	$582,900,000	'	'	'
Conversion Factor, Preferred Stock	'	'	'	'	'	'	'	$0.92	$1.15
Preferred Stock, Liquidation Preference Per Share	'	'	'	'	'	$100	'	'	'
Authorized repurchase of common stock	'	'	'	1,500,000,000	'	'	'	'	'
Remaining stock value of buyback	'	'	'	'	1,100,000,000	'	'	'	'
Proceeds from stock options and stock purchase plan	30,738,000	19,752,000	'	'	'	'	'	'	'
Accrued dividend, restricted stock units	2,300,000	'	'	'	'	'	'	'	'
Paid dividend, restricted stock units	$600,000	'	'	'	'	'	'	'	'

Equity_Schedule_Of_Dividends_D

Equity (Schedule Of Dividends) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Dividends Payable [Line Items]	'	'	'	'
Distribution per share, common stock (in dollars per share)	$0.34	$0.27	$0.66	$0.53
Aggregate Payment Amount, Common Stock	'	'	$127,269,000	$102,984,000
Common Stock [Member] | First Quarter [Member]	'	'	'	'
Dividends Payable [Line Items]	'	'	'	'
Declaration Date	'	'	6-Mar-14	'
Payment Date	'	'	25-Apr-14	'
Record Date	'	'	10-Apr-14	'
Distribution per share, common stock (in dollars per share)	'	'	$0.32	'
Aggregate Payment Amount, Common Stock	'	'	126,600,000	'
Common Stock [Member] | Second Quarter [Member]	'	'	'	'
Dividends Payable [Line Items]	'	'	'	'
Declaration Date	'	'	21-May-14	'
Payment Date	'	'	16-Jul-14	'
Record Date	'	'	17-Jun-14	'
Distribution per share, common stock (in dollars per share)	'	'	$0.34	'
Aggregate Payment Amount, Common Stock	'	'	134,600,000	'
Series A Preferred Stock [Member] | Second Quarter [Member]	'	'	'	'
Dividends Payable [Line Items]	'	'	'	'
Declaration Date	'	'	21-May-14	'
Payment Date	'	'	15-Aug-14	'
Record Date	'	'	1-Aug-14	'
Distribution per share, preferred stock (in dollars per share)	'	'	$1.36	'
Aggregate Payment Amount, Preferred Stock	'	'	$8,100,000	'

Earnings_Per_Share_Schedule_of

Earnings Per Share (Schedule of Earnings Per Basic And Diluted by Common Class) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'
Net income attributable to American Tower Corporation stockholders	$234,431	$99,821	$436,930	$271,228
Dividends declared on preferred stock	-4,375	0	-4,375	0
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION COMMON STOCKHOLDERS	$230,056	$99,821	$432,555	$271,228
Basic weighted average common shares outstanding (in shares)	395,872	395,420	395,511	395,330
Dilutive securities (in shares)	3,716	4,038	3,941	4,329
Diluted weighted average common shares outstanding (in shares)	399,588	399,458	399,452	399,659
Basic net income attributable to American Tower Corporation common stockholders per common share	$0.58	$0.25	$1.09	$0.69
Diluted net income attributable to American Tower Corporation common stockholders per common share	$0.58	$0.25	$1.08	$0.68

Earnings_Per_Share_Earnings_Pe

Earnings Per Share Earnings Per Share (Shares Excluded From Dilutive Effect) (Details)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Restricted stock awards [Member]	'		'		'		'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'		'		'		'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	3		0		1		0
Stock options [Member]	'		'		'		'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'		'		'		'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	2,497		1,229		2,342		860
Mandatory Convertible Preferred Stock [Member]	'		'		'		'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'		'		'		'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	3,733	[1]	0	[1]	1,877	[1]	0	[1]
[1]	Issued on May 12, 2014.

Commitments_And_Contingencies_

Commitments And Contingencies (Narrative) (Details)	0 Months Ended	6 Months Ended
	Jan. 21, 2014	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2014
	INR	USD ($)	At T Transaction [Member]	ALLTEL Transaction [Member]
			USD ($)	USD ($)
			term	towers
			towers
Long-term Purchase Commitment [Line Items]	'	'	'	'
Number of towers leased or subleased	'	'	2,430	'
Lessee leasing arrangements, operating leases, term of contract	'	'	'27 years	'
Number of communications sites acquired	'	'	4	'
Aggregate purchase option price for towers	'	'	$623,500,000	$72,200,000
Purchase price accretion rate (per year)	'	'	10.00%	3.00%
Right to continue to lease space, number of terms	'	'	4	'
Lessee leasing arrangements, operating leases, renewal term	'	'	'5 years	'
Long-term purchase commitment, time period	'	'	'	'15 years
Capital leased assets, number of units	'	'	'	1,800
Cash purchase price per tower	'	'	'	27,500
Purchase price of tower in shares of common stock	'	'	'	769
Value of potential shares payable	'	'	'	122,800,000
India Tax Assessment	22,600,000,000	$369,000,000	'	'

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details)

3 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

12 Months Ended

0 Months Ended

3 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

12 Months Ended

3 Months Ended

6 Months Ended

1 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2013

Dec. 31, 2012

Apr. 03, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Oct. 02, 2013

Jun. 30, 2014

Dec. 31, 2013

Oct. 02, 2013

Jun. 30, 2014

Jun. 30, 2014

Oct. 02, 2013

Oct. 02, 2013

Jan. 31, 2013

Dec. 06, 2013

Aug. 08, 2013

Jun. 30, 2014

Nov. 08, 2013

Aug. 08, 2013

Jun. 30, 2014

Jun. 13, 2014

Jun. 13, 2014

Nov. 29, 2013

Jun. 30, 2014

Dec. 31, 2013

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jul. 30, 2014

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Richland Acquisition [Member]

Richland Acquisition [Member]

Other International Acquisitions 2014 [Member]

Other International Acquisitions 2014 [Member]

Other International Acquisitions 2014 [Member]

Other US Acquisition 2014 [Member]

Other US Acquisition 2014 [Member]

Other US Acquisition 2014 [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

Mexico Axtel Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

BR Towers [Member]

BR Towers [Member]

Z-Sites Acquisition [Member]

Z-Sites Acquisition [Member]

Other International Acquisition 2013 [Member]

Other US Acquisition 2013 [Member]

Colombia Movil Acquisition [Member]

Colombia Movil Acquisition [Member]

Ghana Acquisition [Member]

Subsequent Event [Member]

USD ($)

USD ($)

USD ($)

Brazil [Member]

Mexico [Member]

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

International [Member]

UNITED STATES

USD ($)

Brazil [Member]

Brazil [Member]

Brazil [Member]

Mexico [Member]

Mexico [Member]

Mexico [Member]

USD ($)

BRL

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Other US Acquisition 2014 [Member]

sites

sites

USD ($)

USD ($)

sites

sites

sites

sites

USD ($)

sites

USD ($)

USD ($)

sites

USD ($)

sites

sites

sites

sites

USD ($)

sites

sites

sites

sites

sites

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual

'

'

$10,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business combination pro forma information gross margin of acquiree since acquisition date actual

'

'

7,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Acquisition, Percentage of Voting Interests Acquired

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

'

'

'

'

'

'

'

100.00%

100.00%

'

'

'

'

'

'

'

'

Business combination, acquisition and merger related expenses

4,800,000

3,300,000

14,600,000

16,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of communications sites acquired

'

'

'

'

'

'

'

'

60

'

136

103

299

'

30

'

'

'

'

510

4,860

883

1,937

'

'

1,473

'

'

'

'

238

'

714

55

'

'

'

154

Aggregate purchase price

'

'

'

'

'

'

'

'

385,900,000

'

25,800,000

18,600,000

44,100,000

'

33,600,000

'

4,858,083,000

'

4,858,083,000

'

'

248,500,000

349,000,000

'

342,700,000

436,000,000

'

427,000,000

990,300,000

2,180,000,000

122,800,000

123,900,000

89,800,000

65,600,000

'

'

'

132,500,000

Acquisition deposit in escrow

59,024,000

'

59,024,000

'

'

0

[1]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

59,000,000

130,000,000

'

'

'

'

'

'

'

'

Estimated contingent consideration fair value

'

'

'

'

'

'

'

'

'

'

'

'

'

'

400,000

'

'

5,500,000

5,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

4,100,000

'

24,600,000

24,600,000

500,000

'

Value added tax and other consumption tax receivables

15,730,000

'

15,730,000

'

'

77,016,000

[1]

'

'

'

'

800,000

'

5,600,000

'

'

'

'

'

'

'

'

'

'

'

'

60,300,000

'

59,000,000

'

'

'

'

4,900,000

'

'

'

'

'

Number of property interests acquired

'

'

'

'

'

'

'

'

4

'

'

'

'

'

4

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

23

'

'

'

'

Business acquisition, cost of acquired entity, cash paid

'

'

'

'

'

'

'

'

'

'

'

'

40,300,000

'

33,200,000

'

3,330,462,000

'

3,330,462,000

[2]

'

'

'

'

'

'

436,900,000

'

'

'

'

'

'

'

65,200,000

'

'

'

'

Business Combination, Partial Cash Consideration Transferred

'

'

'

'

'

'

'

'

182,900,000

'

'

'

4,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Consideration Transferred, Other

'

'

'

'

'

'

'

'

'

'

'

'

36,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Acquisition Cost Of Acquired Entity, Purchase Price Reflected In Accounts Payable

'

'

'

'

'

'

'

'

6,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Noncash or Part Noncash Acquisition, Value of Assets Acquired

'

'

'

'

'

'

'

'

'

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

900,000

'

'

'

'

'

'

'

'

'

'

'

'

Noncash or part noncash acquisition, value of liabilities assumed

'

'

'

'

'

'

'

'

196,500,000

196,500,000

'

'

3,800,000

'

'

400,000

1,527,621,000

'

1,527,621,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

400,000

'

'

'

'

Maximum number of communications sites to be acquired

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,790

'

'

1,666

'

2,530

2,530

'

'

'

'

'

'

'

'

Additional Sites To Be Acquired

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,110

2,110

'

'

'

'

'

'

'

'

Business combination, contingent consideration arrangements, range of outcomes, value, low

0

'

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0

0

0

'

Business combination, contingent consideration arrangements, range of outcomes, value, high

44,600,000

'

44,600,000

'

'

'

'

'

'

'

'

'

'

'

400,000

'

'

6,100,000

6,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

37,600,000

37,600,000

500,000

'

Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, purchases

406,000

313,000

406,000

478,000

'

'

'

'

'

'

'

'

'

400,000

'

'

9,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business combination, contingent consideration arrangements, change in amount of contingent consideration, liability

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,400,000

1,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

500,000

1,000,000

'

'

Business acquisition, contingent consideration, actual cash payment

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

700,000

1,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Borrowings under credit facilities

'

'

360,000,000

249,000,000

'

'

'

'

'

'

'

'

'

'

'

'

2,800,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Integration Related Costs

3,200,000

'

5,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Acquisition-related contingent consideration

$31,025,000

$21,218,000

$31,025,000

$21,218,000

$31,342,000

$31,890,000

$25,201,000

$23,711,000

'

'

'

'

'

'

$400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

[2]

Cash consideration includes $14.5 million of an additional purchase price adjustment which was paid to the sellers during the six months ended June 30, 2014 and is reflected in Accrued expenses on the consolidated balance sheet included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.

Acquisitions_Schedule_of_Aggre

Acquisitions (Schedule of Aggregate Purchase Consideration Paid and the Amount of Assets Acquired) (Details) (USD $)

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Apr. 03, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Oct. 02, 2013

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Other International Acquisitions 2014 [Member]

Other International Acquisitions 2014 [Member]

Other US Acquisition 2014 [Member]

Other US Acquisition 2014 [Member]

Other US Acquisition 2014 [Member]

Richland Acquisition [Member]

Richland Acquisition [Member]

Richland Acquisition [Member]

Richland Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

MIPT Acquisition [Member]

Mexico Axtel Acquisition [Member]

Mexico Axtel Acquisition [Member]

Mexico Axtel Acquisition [Member]

Mexico Axtel Acquisition [Member]

Z-Sites Acquisition [Member]

Z-Sites Acquisition [Member]

Z-Sites Acquisition [Member]

Z-Sites Acquisition [Member]

Other International Acquisition 2013 [Member]

Other International Acquisition 2013 [Member]

Other International Acquisition 2013 [Member]

Other International Acquisition 2013 [Member]

Other US Acquisition 2013 [Member]

Other US Acquisition 2013 [Member]

Other US Acquisition 2013 [Member]

Other US Acquisition 2013 [Member]

Other US Acquisition 2013 [Member]

Maximum [Member]

Maximum [Member]

MEXICO

MEXICO

MEXICO

MEXICO

MEXICO

MEXICO

MEXICO

BRAZIL

BRAZIL

BRAZIL

BRAZIL

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Purchase Price Allocation [Member]

Purchase Price Allocation [Member]

Purchase Price Allocation [Member]

Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

MIPT Acquisition [Member]

Other International Acquisitions 2014 [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

NII Holdings Acquisition [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Preliminary Purchase Price Allocation [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Acquired Network Location [Member]

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Value Added Tax Receivable, Current

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$59,000,000

$60,300,000

'

'

'

'

'

'

'

'

Current assets

'

'

7,309,000

'

'

20,000

'

'

'

7,819,000

'

'

'

'

'

'

'

0

[1]

0

[1]

'

'

0

0

'

'

4,863,000

4,863,000

'

'

'

1,220,000

1,220,000

'

'

'

'

'

'

'

59,938,000

[2]

61,183,000

[3]

'

'

0

0

'

'

Cash and cash equivalents

'

'

'

'

'

'

'

'

'

'

'

'

'

35,967,000

[4]

35,967,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted cash

'

'

'

'

'

'

'

'

'

'

'

'

'

30,883,000

[4]

30,883,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accounts receivable, net

'

'

'

'

'

'

'

'

'

'

'

'

'

10,021,000

[4]

10,021,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Prepaid and other current assets

'

'

'

'

'

'

'

'

'

'

'

'

'

35,614,000

[4]

22,875,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Non-current assets

'

'

996,000

'

'

0

'

'

'

0

'

'

'

'

'

'

'

2,626,000

[1]

2,626,000

[1]

'

'

6,436,000

6,157,000

'

'

1,991,000

1,991,000

'

'

'

44,000

44,000

'

'

'

'

'

'

'

10,738,000

[2]

11,969,000

[3]

'

'

7,201,000

4,484,000

'

'

Property and equipment

'

'

29,900,000

'

'

7,696,000

'

'

'

173,686,000

'

'

'

920,782,000

[4]

996,901,000

[5]

'

'

86,100,000

[1]

86,100,000

[1]

'

'

26,881,000

24,832,000

'

'

44,844,000

44,844,000

'

'

'

23,537,000

23,803,000

'

'

'

'

'

'

'

143,680,000

[2]

147,364,000

[3]

'

'

111,094,000

105,784,000

'

'

Intangible assets:

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Customer-related intangible assets

'

'

20,409,000

[6]

'

'

18,928,000

[6]

'

'

'

185,000,000

[6]

'

'

'

2,464,300,000

[4],[7]

2,629,188,000

[5],[7]

'

'

119,392,000

[1],[6]

119,392,000

[1],[6]

'

'

62,286,000

[6]

64,213,000

[6]

'

'

20,590,000

[6]

20,590,000

[6]

'

'

'

29,325,000

[6]

29,325,000

[6]

'

'

'

'

'

'

'

132,897,000

[2],[6]

135,175,000

[3],[6]

'

'

143,037,000

[6]

149,333,000

[6]

'

'

Network location intangible assets

'

'

'

10,772,000

[6]

'

'

3,370,000

[6]

'

'

'

1,800,000

[6]

'

'

'

'

532,000,000

[4],[7]

467,300,000

[5],[7]

'

'

43,031,000

[1],[6]

43,031,000

[1],[6]

'

'

17,350,000

[6]

17,123,000

[6]

'

'

20,727,000

[6]

20,727,000

[6]

'

'

'

7,935,000

[6]

7,607,000

[6]

'

'

'

'

'

'

'

66,069,000

[2],[6]

63,791,000

[3],[6]

'

'

80,568,000

[6]

93,867,000

[6]

Notes receivable and other non-current assets

'

'

'

'

'

'

'

'

'

'

'

'

'

63,682,000

[4]

4,220,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Current liabilities

'

'

-1,307,000

'

'

-439,000

'

'

'

-3,954,000

'

'

'

'

'

'

'

0

[1]

0

[1]

'

'

0

0

'

'

0

0

'

'

'

-454,000

-454,000

'

'

'

'

'

'

'

0

[2]

0

[3]

'

'

0

0

'

'

Accounts payable

'

'

'

'

'

'

'

'

'

'

'

'

'

-9,456,000

[4]

-9,249,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accrued expenses

'

'

'

'

'

'

'

'

'

'

'

'

'

-36,755,000

[4]

-37,004,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accrued interest

'

'

'

'

'

'

'

'

'

'

'

'

'

-3,253,000

[4]

-3,253,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Current portion of long-term obligations

'

'

'

'

'

'

'

'

'

'

'

'

'

-2,820,000

[4]

-2,820,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unearned revenue

'

'

'

'

'

'

'

'

'

'

'

'

'

-35,905,000

[4]

-35,753,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term obligations (4)

'

'

0

[8]

'

'

0

[8]

'

'

'

-201,999,000

[8]

'

'

'

-1,573,366,000

[4],[9]

-1,573,366,000

[5],[9]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Asset retirement obligations

'

'

'

'

'

'

'

'

'

'

'

'

'

-43,089,000

[4]

-43,089,000

[5]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other non-current liabilities

'

'

-6,126,000

'

'

-74,000

'

'

'

-2,922,000

'

'

'

-8,693,000

[4]

-37,326,000

[5]

'

'

-9,377,000

[1]

-9,377,000

[1]

'

'

-1,502,000

-1,502,000

'

'

-8,168,000

-8,168,000

'

'

'

-848,000

-786,000

'

'

'

'

'

'

'

-10,478,000

[2]

-10,478,000

[3]

'

'

-13,188,000

-13,188,000

'

'

Fair value of net assets acquired

'

'

61,953,000

'

'

29,501,000

'

'

'

159,430,000

'

'

'

2,379,912,000

[4]

2,455,495,000

[5]

'

'

241,772,000

[1]

241,772,000

[1]

'

'

111,451,000

110,823,000

'

'

84,847,000

84,847,000

'

'

'

60,759,000

60,759,000

'

'

'

'

'

'

'

402,844,000

[2]

409,004,000

[3]

'

'

328,712,000

340,280,000

'

'

Goodwill

3,854,931,000

3,808,426,000

[10]

4,232,000

[11]

'

'

3,675,000

[11]

'

'

'

29,996,000

[11]

'

'

'

950,550,000

[12],[4]

874,967,000

[12],[5]

'

'

6,751,000

[1],[11]

6,751,000

[1],[11]

'

'

12,493,000

[11]

11,953,000

[11]

'

'

4,970,000

[11]

4,970,000

'

'

'

4,403,000

[11]

4,403,000

'

'

'

'

'

'

'

25,056,000

[11],[2]

27,928,000

[11],[3]

'

'

13,978,000

[11]

8,704,000

[11]

'

'

Acquired finite-live intangible assets, weighted average useful life

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'20 years

'20 years

'

'

'

'

'

'

'

'

'

'

'

Noncash or part noncash acquisition, value of liabilities assumed

'

'

'

'

400,000

'

'

196,500,000

196,500,000

'

'

1,527,621,000

1,527,621,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

400,000

'

'

'

'

'

'

3,800,000

'

'

'

'

'

'

'

'

'

'

Liabilities, Fair Value Adjustment

'

'

'

'

'

'

'

'

$5,500,000

'

'

'

$53,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

The allocation of the purchase price was finalized during the year ended December 31, 2013.

[2]

Current assets includes approximately $59.0 million of value added tax.

[3]

Current assets includes approximately $60.3 million of value added tax.

[4]

Balances are reflected in the accompanying condensed consolidated balance sheets as of June 30, 2014.

[5]

Balances are reflected in the consolidated balance sheets in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.

[6]

Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.

[7]

Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years

[8]

Long-term obligations included $196.5 million of Richland’s existing indebtedness and a fair value adjustment of $5.5 million. The fair value adjustment was based primarily on reported market values using Level 2 inputs.

[9]

Long-term obligations included $1.5 billion of MIPT’s existing indebtedness and a fair value adjustment of $53.0 million. The fair value adjustment was based primarily on reported market values using Level 2 inputs.

[10]

Balances have been revised to reflect purchase accounting measurement period adjustments.

[11]

Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will be deductible for tax purposes.

[12]

Goodwill was allocated to the Company’s domestic and international rental and management segments, as applicable, and the Company expects goodwill recorded will not be deductible for tax purposes.

Acquisitions_Pro_Forma_Informa

Acquisitions (Pro Forma Information) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Acquisition, Pro Forma Information [Abstract]	'	'	'	'
Operating revenues	$1,033,541	$941,291	$2,031,066	$1,879,156
Net income attributable to American Tower Corporation	$230,506	$74,956	$434,176	$212,146
Basic earnings per share (in dollars per share)	$0.58	$0.19	$1.10	$0.54
Diluted earnings per share (in dollars per share)	$0.58	$0.19	$1.09	$0.53

Acquisitions_Schedule_of_Consi

Acquisitions (Schedule of Consideration Transferred) (Details) (MIPT Acquisition [Member], USD $)	0 Months Ended	6 Months Ended
	Oct. 02, 2013	Jun. 30, 2014
MIPT Acquisition [Member]	'	'
Fair Value Of Consideration Transferred [Line Items]	'	'
Partial payment of aggregate purchase price	'	$14,500,000
Aggregate purchase price	4,858,083,000	4,858,083,000
Noncash or part noncash acquisition, value of liabilities assumed	1,527,621,000	1,527,621,000
Business acquisition, cost of acquired entity, cash paid	$3,330,462,000	$3,330,462,000	[1]
[1]	Cash consideration includes $14.5 million of an additional purchase price adjustment which was paid to the sellers during the six months ended June 30, 2014 and is reflected in Accrued expenses on the consolidated balance sheet included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.

Business_Segments_Narrative_De

Business Segments (Narrative) (Details)	6 Months Ended
	Jun. 30, 2014
	segment
Segment Reporting, Measurement Disclosures [Abstract]	'
Number of reportable segments	3

Business_Segments_Summarized_F

Business Segments (Summarized Financial Information Concerning the Company's Reportable Segments) (Details) (USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
Segment Reporting Information [Line Items]	'		'		'		'		'
Segment revenues	$1,031,457		$808,830		$2,015,546		$1,611,558		'
Segment operating expenses	271,822	[1]	205,303	[2]	532,087	[3]	406,631	[4]	'
Interest income, TV Azteca, net	2,662		3,586		5,257		7,129		'
Segment gross margin	762,297		607,113		1,488,716		1,212,056		'
Segment selling, general, administrative and development expense	65,111	[1]	59,057	[2]	124,266	[3]	114,391	[4]	'
Segment operating profit	697,186		548,056		1,364,450		1,097,665		'
Stock-based compensation expense	18,835		17,055		43,439		38,097		'
Other selling, general, administrative and development expense	15,006		24,097		41,780		49,312		'
Depreciation, amortization and accretion	245,427		184,608		491,190		370,412		'
Other expense (principally interest expense and other (expense) income)	174,457		249,630		333,618		387,008		'
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	243,461		72,666		454,423		252,836		'
Total assets	20,847,737		14,339,394		20,847,737		14,339,394		20,245,277
Operating Expense [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Stock-based compensation expense	500		400		1,000		800		'
Selling General Administrative And Development Expense [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Stock-based compensation expense	18,400		16,600		42,500		37,300		'
Operating Segments [Member] | Rental And Management [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Segment revenues	1,005,761		789,199		1,965,881		1,566,632		'
Segment operating expenses	262,841	[1]	197,960	[2]	513,304	[3]	389,009	[4]	'
Interest income, TV Azteca, net	2,662		3,586		5,257		7,129		'
Segment gross margin	745,582		594,825		1,457,834		1,184,752		'
Segment selling, general, administrative and development expense	62,785	[1]	56,733	[2]	119,410	[3]	109,166	[4]	'
Segment operating profit	682,797		538,092		1,338,424		1,075,586		'
Total assets	20,615,600		14,032,820		20,615,600		14,032,820		'
Operating Segments [Member] | Rental And Management [Member] | Domestic [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Segment revenues	659,743		521,043		1,295,522		1,036,719		'
Segment operating expenses	126,340	[1]	95,208	[2]	247,849	[3]	187,041	[4]	'
Interest income, TV Azteca, net	0		0		0		0		'
Segment gross margin	533,403		425,835		1,047,673		849,678		'
Segment selling, general, administrative and development expense	28,313	[1]	24,243	[2]	55,722	[3]	47,141	[4]	'
Segment operating profit	505,090		401,592		991,951		802,537		'
Total assets	14,149,220		8,618,294		14,149,220		8,618,294		'
Operating Segments [Member] | Rental And Management [Member] | International [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Segment revenues	346,018		268,156		670,359		529,913		'
Segment operating expenses	136,501	[1]	102,752	[2]	265,455	[3]	201,968	[4]	'
Interest income, TV Azteca, net	2,662		3,586		5,257		7,129		'
Segment gross margin	212,179		168,990		410,161		335,074		'
Segment selling, general, administrative and development expense	34,472	[1]	32,490	[2]	63,688	[3]	62,025	[4]	'
Segment operating profit	177,707		136,500		346,473		273,049		'
Total assets	6,466,380		5,414,526		6,466,380		5,414,526		'
Operating Segments [Member] | Network Development Services [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Segment revenues	25,696		19,631		49,665		44,926		'
Segment operating expenses	8,981	[1]	7,343	[2]	18,783	[3]	17,622	[4]	'
Interest income, TV Azteca, net	0		0		0		0		'
Segment gross margin	16,715		12,288		30,882		27,304		'
Segment selling, general, administrative and development expense	2,326	[1]	2,324	[2]	4,856	[3]	5,225	[4]	'
Segment operating profit	14,389		9,964		26,026		22,079		'
Total assets	58,611		48,603		58,611		48,603		'
Operating Segments [Member] | All Other Segments [Member]	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Stock-based compensation expense	18,835		17,055		43,439		38,097		'
Other selling, general, administrative and development expense	15,006		24,097		41,780		49,312		'
Depreciation, amortization and accretion	245,427		184,608		491,190		370,412		'
Other expense (principally interest expense and other (expense) income)	174,457		249,630		333,618		387,008		'
Total assets	$173,526		$257,971		$173,526		$257,971		'
[1]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.5 million and $18.4 million, respectively.
[2]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.4 million and $16.6 million, respectively.
[3]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.0 million and $42.5 million, respectively.
[4]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.8 million and $37.3 million, respectively.