American Tower (AMT) 10-K 24 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 13, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Entity Registrant Name	AMERICAN TOWER CORP /MA/
Entity Central Index Key	1053507
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		396,708,636
Entity Public Float			$35.30
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
CURRENT ASSETS:
Cash and cash equivalents	$313,492		$293,576
Restricted cash	160,206		152,916
Short-term investments	6,302	[1]	18,612
Accounts receivable, net	198,714		151,165
Prepaid and other current assets	254,622		347,417	[2]
Deferred income taxes	14,632		22,401
Total current assets	947,968		986,087
PROPERTY AND EQUIPMENT, net	7,626,817		7,177,728	[2]
GOODWILL	4,017,082		3,854,802	[3]
OTHER INTANGIBLE ASSETS, net	6,889,331		6,570,119	[4]
DEFERRED INCOME TAXES	253,186		266,909
DEFERRED RENT ASSET	1,030,707		918,847
NOTES RECEIVABLE AND OTHER NON-CURRENT ASSETS	566,454		509,173	[2]
TOTAL	21,331,545		20,283,665	[3]
CURRENT LIABILITIES:
Accounts payable	90,366		172,938
Accrued expenses	417,754		421,188	[2]
Distributions payable	159,864		575
Accrued interest	130,265		105,751
Current portion of long-term obligations	897,624		70,132
Unearned revenue	233,819		162,079
Total current liabilities	1,929,692		932,663
LONG-TERM OBLIGATIONS	13,711,084		14,408,146
ASSET RETIREMENT OBLIGATIONS	609,035		549,548	[4]
OTHER NON-CURRENT LIABILITIES	1,028,382		803,268	[2]
Total liabilities	17,278,193		16,693,625
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; 399,508,751 and 397,674,350 shares issued; and 396,698,725 and 394,864,324 shares outstanding, respectively	3,995		3,976
Additional paid-in capital	5,788,786		5,130,616
Distributions in excess of earnings	-837,320		-1,081,467
Accumulated other comprehensive loss	-794,221		-311,220
Treasury stock (2,810,026 shares at cost)	-207,740		-207,740
Total American Tower Corporation equity	3,953,560		3,534,165
Noncontrolling interest	99,792		55,875
Total equity	4,053,352		3,590,040
TOTAL	$21,331,545		$20,283,665
[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.
[4]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
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	399,508,751	397,674,350
Common stock, shares outstanding	396,698,725	394,864,324
Treasury stock, shares	2,810,026	2,810,026
Convertible Preferred Stock Subject to Mandatory Redemption
Class of Stock [Line Items]
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
Preferred stock, rate of preferred stock	5.25%

CONSOLIDATED_STATEMENTS_OF_OPE

CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUES:
Rental and management	$4,006,854	$3,287,090	$2,803,490
Network development services	93,194	74,317	72,470
Total operating revenues	4,100,048	3,361,407	2,875,960
OPERATING EXPENSES:
Rental and management (including stock-based compensation expense of $1,397, $977 and $793, respectively)	1,056,177	828,742	686,681
Network development services (including stock-based compensation expense of $440, $567 and $968, respectively)	38,088	31,131	35,798
Depreciation, amortization and accretion	1,003,802	800,145	644,276
Selling, general, administrative and development expense (including stock-based compensation expense of $78,316, $66,594 and $50,222, respectively)	446,542	415,545	327,301
Other operating expenses	68,517	71,539	62,185
Total operating expenses	2,613,126	2,147,102	1,756,241
OPERATING INCOME	1,486,922	1,214,305	1,119,719
OTHER INCOME (EXPENSE):
Interest income	14,002	9,706	7,680
Interest expense	-580,234	-458,296	-401,665
Loss on retirement of long-term obligations	-3,473	-38,701	-398
Other expense (including unrealized foreign currency losses of $49,319, $211,722 and $34,330, respectively)	-62,060	-207,500	-38,300
Total other expense	-621,218	-672,556	-418,425
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INCOME ON EQUITY METHOD INVESTMENTS	865,704	541,749	701,294
Income tax provision	-62,505	-59,541	-107,304
Income on equity method investments	0	0	35
NET INCOME	803,199	482,208	594,025
Net loss attributable to noncontrolling interest	21,711	69,125	43,258
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION STOCKHOLDERS	824,910	551,333	637,283
Dividends declared on preferred stock	-23,888	0	0
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION STOCKHOLDERS	801,022	551,333	637,283
NET INCOME PER COMMON SHARE AMOUNTS:
Basic net income attributable to American Tower Corporation common stockholders (in dollars per share)	$2.02	$1.40	$1.61
Diluted net income attributable to American Tower Corporation common stockholders (in dollars per share)	$2	$1.38	$1.60
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
BASIC (in shares)	395,958	395,040	394,772
DILUTED (in shares)	400,086	399,146	399,287
TV Azteca
OTHER INCOME (EXPENSE):
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively	10,547	22,235	14,258
Interest expense	($1,482)	($1,483)	($1,485)

CONSOLIDATED_STATEMENTS_OF_OPE1

CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock-based compensation expense	$80,153	$68,138	$51,983
Interest Expense	580,234	458,296	401,665
TV Azteca
Interest Expense	1,482	1,483	1,485
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively	10,547	22,235	14,258
Rental And Management
Stock-based compensation expense	1,397	977	793
Network Development Services
Stock-based compensation expense	440	567	968
Selling General Administrative And Development Expense
Stock-based compensation expense	78,316	66,594	50,222
Other Expense [Member]
Unrealized foreign currency (losses) gains	($49,319)	($211,722)	($34,330)

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$803,199	$482,208	$594,025
Other comprehensive (loss) income:
Changes in fair value of cash flow hedges, net of taxes of $151, $(374) and $905, respectively	-1,931	1,107	-5,315
Reclassification of unrealized losses on cash flow hedges to net income, net of taxes of $(158), $(237) and $(208), respectively	3,448	2,572	1,132
Reclassification of unrealized losses on available-for-sale securities to net income	0	0	495
Foreign currency translation adjustments, net of taxes of $14,247, $9,207 and $7,677, respectively	-526,890	-135,079	-58,387
Other comprehensive loss	-525,373	-131,400	-62,075
Comprehensive income	277,826	350,808	531,950
Comprehensive loss attributable to noncontrolling interest	64,083	72,652	64,603
Comprehensive income attributable to American Tower Corporation stockholders	$341,909	$423,460	$596,553

CONSOLIDATED_STATEMENTS_OF_COM1

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Reclassification of unrealized losses on cash flow hedges to net income, tax	$158	$237	$208
Other comprehensive income (loss), avaliable-for-sale securities, tax	0	0	0
Foreign currency translation adjustments, tax	-14,247	-9,207	-7,677
Net change in fair value of cash flow hedges, tax	($151)	$374	($905)

CONSOLIDATED_STATEMENTS_OF_EQU

CONSOLIDATED STATEMENTS OF EQUITY (USD $)	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Earnings (Distributions) in Excess of Distributions (Earnings)	Noncontrolling Interest	Convertible Preferred Stock Subject to Mandatory Redemption	Series A Preferred Stock
In Thousands, except Share data, unless otherwise specified	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)		Convertible Preferred Stock Subject to Mandatory Redemption
									Preferred Stock
									USD ($)
BALANCE at Dec. 31, 2011	$3,410,142	$3,936	$0	$4,903,800	($142,617)	($1,477,899)	$122,922
BALANCE (shares) at Dec. 31, 2011		393,642,079	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation related activity (shares)		2,233,390
Stock-based compensation related activity	103,820	22		103,798
Issuance of common stock-Stock Purchase Plan (shares)		87,749
Issuance of common stock—stock purchase plan	4,527	1		4,526
Treasury stock activity (shares)			-872,005
Treasury stock activity	-62,728		-62,728
Net change in fair value of cash flow hedges, net of tax	-5,315				-4,733		-582
Reclassification of unrealized losses on cash flow hedges to net income	1,132				998		134
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss), Net of Tax	-495				-495		0
Foreign currency translation adjustment, net of tax	-58,387				-37,490		-20,897
Contributions from noncontrolling interest	53,341						53,341
Distributions to noncontrolling interest	-580						-580
Dividends/distributions declared	-356,291					-356,291
Dividends declared on preferred stock	0
Net income	594,025					637,283	-43,258
BALANCE at Dec. 31, 2012	3,684,181	3,959	-62,728	5,012,124	-183,347	-1,196,907	111,080
BALANCE (shares) at Dec. 31, 2012		395,963,218	-872,005
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation related activity (shares)		1,633,380
Stock-based compensation related activity	113,582	16		113,566
Issuance of common stock-Stock Purchase Plan (shares)		77,752
Issuance of common stock—stock purchase plan	4,927	1		4,926
Treasury stock activity (shares)			-1,938,021
Treasury stock activity	-145,012		-145,012
Net change in fair value of cash flow hedges, net of tax	1,107				867		240
Reclassification of unrealized losses on cash flow hedges to net income	2,572				2,420		152
Foreign currency translation adjustment, net of tax	-135,079				-131,160		-3,919
Contributions from noncontrolling interest	18,020						18,020
Distributions to noncontrolling interest	-573						-573
Dividends/distributions declared	-435,893					-435,893
Dividends declared on preferred stock	0
Net income	482,208					551,333	-69,125
BALANCE at Dec. 31, 2013	3,590,040	3,976	-207,740	5,130,616	-311,220	-1,081,467	55,875
BALANCE Preferred (shares) at Dec. 31, 2013								0
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)		1,753,286
Stock-based compensation related activity	119,734	18		119,716
Issuance of common stock-Stock Purchase Plan (shares)		81,115
Issuance of common stock—stock purchase plan	5,718	1		5,717
Issuance of preferred stock (shares)									6,000,000
Issuance of preferred stock	582,659			582,599					60
Net change in fair value of cash flow hedges, net of tax	-1,931				-1,966		35
Reclassification of unrealized losses on cash flow hedges to net income	3,448				3,288		160
Foreign currency translation adjustment, net of tax	-526,890				-484,323		-42,567
Contributions from noncontrolling interest	123,526						123,526
Distributions to noncontrolling interest	-566						-566
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	-64,822			-49,862			-14,960
Dividends/distributions declared	-556,875					-556,875
Dividends declared on preferred stock	-23,888					-23,888
Net income	803,199					824,910	-21,711
BALANCE at Dec. 31, 2014	$4,053,352	$3,995	($207,740)	$5,788,786	($794,221)	($837,320)	$99,792		$60
BALANCE Preferred (shares) at Dec. 31, 2014								6,000,000	6,000,000
BALANCE (shares) at Dec. 31, 2014	396,698,725	399,508,751	-2,810,026

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$803,199	$482,208	$594,025
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation, amortization and accretion	1,003,802	800,145	644,276
Stock-based compensation expense	80,153	68,138	51,983
Decrease (increase) in restricted cash	7,522	-52,717	-26,500
Loss on investments, unrealized foreign currency loss and other non-cash expense	65,881	222,390	60,002
Impairments, net loss on sale of long-lived assets, non-cash restructuring and merger related expenses	26,143	32,672	34,280
Loss on early retirement of long-term obligations	3,379	35,288	0
Amortization of deferred financing costs, debt discounts and premiums and other non-cash interest	-4,870	7,596	11,090
Provision for losses on accounts receivable	-1,748	-1,410	-4,155
Deferred income taxes	1,384	-29,485	29,300
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	-84,529	-19,080	-43,679
Prepaid and other assets	-1,437	-96,038	84,640
Deferred rent asset	-122,230	-145,689	-164,219
Accounts payable and accrued expenses	34,711	83,746	21,880
Accrued interest	45,514	51,076	25,031
Unearned revenue	218,393	108,487	68,015
Deferred rent liability	38,378	30,246	33,707
Other non-current liabilities	20,944	21,474	-5,285
Cash provided by operating activities	2,134,589	1,599,047	1,414,391
CASH FLOWS FROM INVESTING ACTIVITIES
Payments for purchase of property and equipment and construction activities	-974,404	-724,532	-568,048
Payments for acquisitions, net of cash acquired	-1,010,637	-4,461,764	-1,997,955
Net proceeds from sale of assets	15,464	0	0
Proceeds from sales of short-term investments, available-for-sale securities and other long-term assets	1,434,831	421,714	374,682
Payments for short-term investments	-1,395,316	-427,267	-352,306
Deposits, restricted cash and other	-19,486	18,512	-14,758
Cash used in investing activities	-1,949,548	-5,173,337	-2,558,385
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from (repayments of) short-term borrowings, net	0	8,191	-55,264
Borrowings under credit facilities	2,187,000	3,507,000	2,582,000
Proceeds from issuance of senior notes, net	1,415,844	2,221,792	698,670
Proceeds from term loan	0	1,500,000	750,000
Proceeds from other long-term borrowings	102,070	402,688	177,299
Proceeds from issuance of Securities in Securitization transaction, net	0	1,778,496	0
Repayments of notes payable, credit facilities and capital leases	-3,903,144	-5,337,339	-2,658,566
Contributions from noncontrolling interest holders, net	9,098	17,447	52,761
Purchases of common stock	0	-145,012	-62,728
Proceeds from stock options and stock purchase plan	62,276	45,496	55,441
Distributions paid on common stock	-404,631	-434,687	-355,574
Distributions paid on preferred stock	-16,013	0	0
Proceeds from the issuance of preferred stock, net	583,105	0	0
Purchase of preferred stock assumed in acquisition	-59,111	0	0
Payment for early retirement of long-term obligations	-11,593	-29,234	0
Deferred financing costs and other financing activities	-34,670	-9,273	-13,673
Purchase of noncontrolling interest	-64,822	0	0
Cash (used in) provided by financing activities	-134,591	3,525,565	1,170,366
Net effect of changes in foreign currency exchange rates on cash and cash equivalents	-30,534	-26,317	12,055
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	19,916	-75,042	38,427
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	293,576	368,618	330,191
CASH AND CASH EQUIVALENTS, END OF YEAR	$313,492	$293,576	$368,618

Business_and_Summary_of_Signif

Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Summary of Significant Accounting Policies	BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Business—American Tower Corporation is, through its various subsidiaries (collectively, “ATC” or the “Company”), a global independent owner, operator and developer of communications real estate. The Company’s primary business is the leasing of 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.
	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 operates as a real estate investment trust for U.S. federal income tax purposes (“REIT”) and, therefore, is generally not subject to federal income taxes on its income and gains that it 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 taxable REIT subsidiaries (“TRSs”). 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 use of TRSs enables the Company to continue to engage in certain businesses while complying with REIT qualification requirements. 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 QRS as part of its REIT taxable income for the purpose of computing its REIT distribution requirements. During the year ended December 31, 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 a result, as of December 31, 2014, the Company’s QRSs include its domestic tower leasing business, most of its operations in Costa Rica, Germany and Mexico and a portion of its network development services segment and indoor DAS networks business.
	Principles of Consolidation and Basis of Presentation—The accompanying 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 consolidated financial statements and accompanying notes. Actual results may differ from those estimates, and such differences could be material to the accompanying consolidated financial statements. The significant estimates in the accompanying 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.
	Concentrations of Credit Risk—The Company is subject to concentrations of credit risk related to its cash and cash equivalents, notes receivable, accounts receivable, deferred rent asset and derivative financial instruments. The Company mitigates its risk with respect to cash and cash equivalents and derivative financial instruments by maintaining its deposits and contracts at high quality financial institutions and monitoring the credit ratings of those institutions.
	The Company derives the largest portion of its revenues, corresponding accounts receivable and the related deferred rent asset from a relatively small number of tenants in the telecommunications industry, and approximately 56% of its current year revenues are derived from four tenants. In addition, the Company has concentrations of credit risk in certain geographic areas.
	The Company mitigates its concentrations of credit risk with respect to notes and trade receivables and the related deferred rent assets by actively monitoring the credit worthiness of its borrowers and tenants. In recognizing customer revenue, the Company must assess the collectibility of both the amounts billed and the portion recognized in advance of billing on a straight-line basis. This assessment takes tenant credit risk and business and industry conditions into consideration to ultimately determine the collectibility of the amounts billed. To the extent the amounts, based on management’s estimates, may not be collectible, recognition is deferred until such point as collectibility is determined to be reasonably assured. Any amounts that were previously recognized as revenue and subsequently determined to be uncollectible are charged to bad debt expense included in Selling, general, administrative and development expense in the accompanying consolidated statements of operations.
	Accounts receivable is reported net of allowances for doubtful accounts related to estimated losses resulting from a tenant’s inability to make required payments and allowances for amounts invoiced whose collectibility is not reasonably assured. These allowances are generally estimated based on payment patterns, days past due and collection history, and incorporate changes in economic conditions that may not be reflected in historical trends, such as tenants in bankruptcy, liquidation or reorganization. Receivables are written-off against the allowances when they are determined to be uncollectible. Such determination includes analysis and consideration of the particular conditions of the account. Changes in the allowances were as follows for the years ended December 31, (in thousands):
		2014			2013			2012
	Balance as of January 1	$	19,895		$	20,406		$	24,412
	Current year increases	8,243			7,025			8,028
	Write-offs, net of recoveries and other	(10,832		)	(7,536		)	(12,034		)
	Balance as of December 31	$	17,306		$	19,895		$	20,406
	Functional Currency—The functional currency of each of the Company’s foreign operating subsidiaries is the respective local currency, except for Costa Rica, 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 consolidated balance sheets and included as a component of comprehensive income.
	Transactional gains and losses on foreign currency transactions are reflected in Other expense in the 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 consolidated balance sheets and included as a component of comprehensive income. During the year ended December 31, 2014, the Company recorded unrealized foreign currency losses of $468.6 million, of which $419.3 million was recorded in AOCI and $49.3 million was recorded in Other expense.
	Cash and Cash Equivalents—Cash and cash equivalents include cash on hand, demand deposits and short-term investments, including money market funds, with remaining maturities of three months or less when acquired, whose cost approximates fair value.
	Restricted Cash—The Company classifies as restricted cash all cash pledged as collateral to secure obligations and all cash whose use is otherwise limited by contractual provisions, including cash on deposit in reserve accounts relating to the (i) Secured Tower Revenue Securities, Series 2013-1A and Series 2013-2A issued in the Company’s 2013 securitization transaction (the “Securities”), (ii) Secured Cellular Site Revenue Notes, Series 2010-1 Class C, Series 2010-2 Class C and Series 2010-2 Class F (collectively, the “Unison Notes”), assumed by the Company in connection with an acquisition and (iii) six series, consisting of eleven separate classes, of Secured Tower Revenue Notes, of which the Company repaid one series, consisting of two classes, in August 2014 (the remaining notes, the “GTP Notes”) assumed by the Company in connection with an acquisition.
	Short-Term Investments—Short-term investments consists of highly-liquid investments with original maturities in excess of three months.
	Property and Equipment—Property and equipment is recorded at cost or, in the case of acquired properties, at estimated fair value on the date acquired. Cost for self-constructed towers includes direct materials and labor, capitalized interest and certain indirect costs associated with construction of the tower, such as transportation costs, employee benefits and payroll taxes. The Company begins the capitalization of costs during the pre-construction period, which is the period during which costs are incurred to evaluate the site, and continues to capitalize costs until the tower is substantially completed and ready for occupancy by a tenant. Labor costs capitalized for the years ended December 31, 2014, 2013 and 2012 were $48.5 million, $44.1 million and $41.6 million, respectively. Interest costs capitalized for the years ended December 31, 2014, 2013 and 2012 were $2.8 million, $1.8 million and $1.9 million, respectively.
	Expenditures for repairs and maintenance are expensed as incurred. Augmentation and improvements that extend an asset’s useful life or enhance capacity are capitalized.
	Depreciation is recorded using the straight-line method over the assets’ estimated useful lives. Towers and related assets on leased land are depreciated over the shorter of the estimated useful life of the asset or the term of the corresponding ground lease, taking into consideration lease renewal options and residual value.
	Towers or assets acquired through capital leases are reflected in Property and equipment, net at the present value of future minimum lease payments or the fair value of the leased asset at the inception of the lease. Property and equipment, network location intangibles and assets held under capital leases are amortized over the shorter of the applicable lease term or the estimated useful life of the respective assets for periods generally not exceeding twenty years.
	Goodwill and Other Intangible Assets—The Company reviews goodwill for impairment at least annually (as of December 31) or whenever events or circumstances indicate the carrying value of an asset may not be recoverable.
	Goodwill is recorded in the applicable segment and assessed for impairment at the reporting unit level. The Company utilizes the two-step impairment test when testing goodwill for impairment and employs a discounted cash flow analysis. The key assumptions utilized in the discounted cash flow analysis include current operating performance, terminal sales growth rate, management’s expectations of future operating results and cash requirements, the current weighted average cost of capital and an expected tax rate. Under the first step of this test, the Company compares the fair value of the reporting unit, as calculated under an income approach using future discounted cash flows, to the carrying amount of the applicable reporting unit. If the carrying amount exceeds the fair value, the Company conducts the second step of this test, in which the implied fair value of the applicable reporting unit’s goodwill is compared to the carrying amount of that goodwill. If the carrying amount of goodwill exceeds its implied fair value, an impairment loss would be recognized for the amount of the excess.
	During the years ended December 31, 2014, 2013 and 2012, no potential impairment was identified under the first step of the test, as the fair value of each of the reporting units was in excess of its carrying amount.
	Intangible assets that are separable from goodwill and are deemed to have a definite life are amortized over their useful lives, generally ranging from three to twenty years and are evaluated separately for impairment at least annually or whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable.
	Deferred Rent Asset—The Company’s deferred rent asset is associated with non-cancellable tenant leases that contain fixed escalation clauses over the terms of the applicable lease in which revenue is recognized on a straight-line basis over the lease term.
	Notes Receivable and Other Non-Current Assets—Notes receivable and other non-current assets primarily consists of prepaid ground lease assets, value added tax receivable, notes receivable from TV Azteca, long-term deposits, favorable leasehold interests and other non-current assets.
	Derivative Financial Instruments—Derivatives are recorded on the consolidated balance sheet at fair value. If a derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are recorded in AOCI, as well as a component of comprehensive income, and are recognized in the results of operations when the hedged item affects earnings. Changes in fair value of the ineffective portions of cash flow hedges are recognized 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 that the change occurs.
	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.
	The Company assesses, both at the inception of the hedge and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in cash flows of hedged items. The Company does not hold derivatives for trading purposes.
	The Company may also enter into foreign currency financial instruments in anticipation of future transactions in order to minimize the risk of currency fluctuations. These transactions do not typically qualify for hedge accounting, and as a result, the associated gains and losses are recognized in Other income (expense) in the consolidated statements of operations.
	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.
	Discount and Premium on Notes—The Company amortizes the discounts and premiums on its notes using the effective interest method over the term of the obligation. Such amortization is reflected in Interest expense and Interest income, TV Azteca, net in the accompanying consolidated statements of operations.
	Asset Retirement Obligations—When required, the Company recognizes the fair value of obligations to remove its tower assets and remediate the leased land upon which certain of its tower assets are located. Generally, the associated retirement costs are capitalized as part of the carrying amount of the related tower assets and depreciated over their estimated useful lives and the liability is accreted through the obligation’s estimated settlement date. Fair value estimates of asset retirement obligations generally involve discounting of estimated future cash flows. Periodic accretion of such liabilities due to the passage of time is included in Depreciation, amortization and accretion in the consolidated statements of operations. Adjustments are also made to the asset retirement obligation liability to reflect changes in the estimates of timing and amount of expected cash flows, with an offsetting adjustment made to the related tangible long-lived asset. The significant assumptions used in estimating the Company’s aggregate asset retirement obligation are: timing of tower removals; cost of tower removals; timing and number of land lease renewals; expected inflation rates; and credit-adjusted, risk-free interest rates that approximate the Company’s incremental borrowing rate.
	Income Taxes—As a REIT, the Company is generally not subject to federal income taxes on income and gains distributed to the Company’s stockholders. However, the Company remains obligated to pay income taxes on earnings from domestic TRSs. In addition, the Company’s international assets and operations continue to be subject to taxation in the foreign jurisdictions where those assets are held or where those operations are conducted, including those designated as QRSs for federal income tax purposes. Accordingly, the consolidated financial statements reflect provisions for federal, state, local and foreign income taxes. The Company recognizes deferred tax assets and liabilities for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis, as well as operating loss and tax credit carryforwards. The Company measures deferred tax assets and liabilities using enacted tax rates expected to apply to taxable income in the years in which those temporary differences and carryforwards are expected to be recovered or settled. The effect on deferred tax assets and liabilities as a result of a change in tax rates is recognized in income in the period that includes the enactment date.
	The Company periodically reviews its deferred tax assets, and records a valuation allowance 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. Valuation allowances would be reversed as a reduction to the provision for income taxes if related deferred tax assets are deemed realizable based on changes in facts and circumstances relevant to the assets’ recoverability.
	The Company classifies uncertain tax positions as non-current income tax liabilities unless expected to be paid within one year. The Company reports penalties and tax-related interest expense as a component of the income tax provision and interest income from tax refunds as a component of Other income (expense) in the consolidated statements of operations.
	Other Comprehensive Income (Loss)—Other comprehensive income (loss) refers to items excluded from net income that are recorded as an adjustment to equity, net of tax. The Company’s other comprehensive income (loss) is primarily comprised of changes in fair value of effective derivative cash flow hedges, foreign currency translation adjustments and reclassification of unrealized losses on effective derivative cash flow hedges.
	Treasury Stock—The Company records repurchases of its common stock using the cost method, whereby the purchase price, including legal costs and commissions, is recorded in a contra equity account, Treasury stock. The equity accounts from which the shares were originally issued are not adjusted for any treasury stock purchases unless and until such time as the shares are formally retired or reissued. As part of the Company’s conversion to a REIT, all treasury stock outstanding at the time was retired.
	Distributions—As a REIT, the Company must annually distribute to its stockholders an amount equal to at least 90% of its REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain). Generally, the Company has distributed, and expects to continue to distribute all or substantially all of its REIT taxable income after taking into consideration its utilization of net operating loss carryforwards (“NOLs”). During the years ended December 31, 2014, 2013 and 2012, the Company declared regular cash distributions to its common stockholders of an aggregate of $554.6 million, or $1.40 per share, $434.5 million, or $1.10 per share, and $355.6 million, or $0.90 per share, respectively.
	During the year ended December 31, 2014, the Company declared an aggregate of $23.9 million, or $3.98 per share in cash distributions to its preferred stockholders.
	The amount, timing and frequency of future distributions will be at the sole discretion of the Board of Directors and will be declared based upon various factors, a number of which may be beyond the Company’s control, including the financial condition and operating cash flows, the amount required to maintain its qualification for taxation as a REIT and reduce any income and excise taxes that the Company otherwise would be required to pay, limitations on distributions in the Company’s existing and future debt and preferred equity instruments, the Company’s ability to utilize NOLs to offset the Company’s distribution requirements, limitations on its ability to fund distributions using cash generated through its TRSs and other factors that the Board of Directors may deem relevant.
	Acquisitions—For acquisitions that meet the definition of a business combination, the Company applies the acquisition method of accounting where assets acquired and liabilities assumed are recorded at fair value at the date of each acquisition, and the results of operations are included with those of the Company from the dates of the respective acquisitions. Any excess of the purchase price paid by the Company over the amounts recognized for assets acquired and liabilities assumed is recorded as goodwill. The Company continues to evaluate acquisitions for a period not to exceed one year after the applicable acquisition date of each transaction to determine whether any additional adjustments are needed to the allocation of the purchase price paid for the assets acquired and liabilities assumed. The fair value of the assets acquired and liabilities assumed is typically determined by using either estimates of replacement costs or discounted cash flow valuation methods. When determining the fair value of tangible assets acquired, the Company must estimate the cost to replace the asset with a new asset taking into consideration such factors as age, condition and the economic useful life of the asset. When determining the fair value of intangible assets acquired, the Company must estimate the applicable discount rate and the timing and amount of future customer cash flows, including rate and terms of renewal and attrition.
	Revenue Recognition—The Company’s revenue from leasing arrangements, including fixed escalation clauses present in non-cancellable lease agreements, is reported on a straight-line basis over the term of the respective leases when collectibility is reasonably assured. Escalation clauses tied to the Consumer Price Index (“CPI”) or other inflation-based indices, and other incentives present in lease agreements with the Company’s tenants are excluded from the straight-line calculation. Total rental and management straight-line revenues for the years ended December 31, 2014, 2013 and 2012 approximated $123.7 million, $147.7 million and $165.8 million, respectively. Amounts billed upfront in connection with the execution of lease agreements are initially deferred and reflected in Unearned revenue in the accompanying consolidated balance sheets and recognized as revenue over the terms of the applicable leases. Amounts billed or received for services prior to being earned are deferred and reflected in Unearned revenue in the accompanying consolidated balance sheets until the criteria for recognition have been met.
	Network development services revenues are derived under contracts or arrangements with customers that provide for billings either on a fixed price basis or a variable price basis, which includes factors such as time and expenses. Revenues are recognized as services are performed, and include estimates for percentage completed. Amounts billed or received for services prior to being earned are deferred and reflected in Unearned revenue in the accompanying consolidated balance sheets until the criteria for recognition have been met.
	Rent Expense—Many of the leases underlying the Company’s tower sites have fixed rent escalations, which provide for periodic increases in the amount of ground rent payable by the Company over time. In addition, certain of the Company’s tenant leases require the Company to exercise available renewal options pursuant to the underlying ground lease if the tenant exercises its renewal option. The Company calculates straight-line ground rent expense for these leases based on the fixed non-cancellable term of the underlying ground lease plus all periods, if any, for which failure to renew the lease imposes an economic penalty to the Company such that renewal appears to be reasonably assured.
	Total rental and management straight-line ground rent expense for the years ended December 31, 2014, 2013 and 2012 approximated $38.4 million, $29.7 million and $33.7 million, respectively. The Company’s liability for straight-line ground rent expense is recorded in Other non-current liabilities. The Company records prepaid ground rent in Prepaid and other current assets and Notes receivable and other non-current assets in the accompanying consolidated balance sheets according to the anticipated period of benefit.
	Selling, General, Administrative and Development Expense—Selling, general and administrative expense consists of overhead expenses related to the Company’s rental and management and services operations and corporate overhead costs not specifically allocable to any of the Company’s individual business operations. Development expense consists of costs related to the Company’s acquisition efforts, costs associated with new business initiatives and project cancellation costs.
	Stock-Based Compensation—Stock-based compensation expense is measured at the accounting measurement date based on the fair value of the award and is recognized as an expense over the service period, which generally represents the vesting period. 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 that 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. Accordingly, for grants made on or after January 1, 2013, the Company recognizes compensation expense for all stock-based compensation over the shorter of (i) the four-year vesting period or (ii) the period from the date of grant to the date the employee becomes eligible for such retirement benefits, which may occur upon grant. The expense recognized over the service period includes an estimate of awards that will not fully vest and be forfeited. The fair value of stock options is determined using the Black-Scholes option-pricing model and the fair value of restricted stock units is based on the fair value of the Company’s common stock on the date of grant. The Company recognizes stock-based compensation expense in either Selling, general, administrative and development expense, costs of operations or as part of the costs associated with the construction of the tower assets.
	Litigation Costs—The Company periodically becomes involved in various claims and lawsuits that are incidental to its business. The Company regularly monitors the status of pending legal actions to evaluate both the magnitude and likelihood of any potential loss. The Company accrues for these potential losses when it is probable that a liability has been incurred and the amount of loss, or possible range of loss, can be reasonably estimated. Should the ultimate losses on contingencies or litigation vary from estimates, adjustments to those liabilities may be required. The Company also incurs legal costs in connection with these matters and records estimates of these expenses, which are reflected in Selling, general, administrative and development expense in the accompanying consolidated statements of operations.
	Other Operating Expenses—Other operating expenses includes the costs incurred by the Company in conjunction with acquisitions and mergers (including changes in estimated fair value of contingent consideration), impairments on long-lived assets and gains and losses recognized upon the disposal of long-lived assets and other discrete items of a non-recurring nature.
	The Company reviews long-lived assets, including intangible assets subject to amortization, for impairment whenever events, changes in circumstances or other evidence indicate that the carrying amount of the Company’s assets may not be recoverable.
	The Company reviews its tower portfolio and network location intangible assets for indications of impairment on an individual tower basis. Impairments primarily result from a tower not having current tenant leases or from having expenses in excess of revenues. The Company monitors its customer-related intangible assets on a customer by customer basis for indicators of impairment, such as high levels of turnover or attrition, non-renewal of a significant number of contracts, or the cancellation or termination of a relationship. The Company assesses recoverability by determining whether the carrying amount of the related assets will be recovered, either through projected undiscounted future cash flows or anticipated proceeds from sales of the assets. If the Company determines that the carrying amount of an asset may not be recoverable, the Company will measure any impairment loss based on the projected future discounted cash flows to be provided from the asset or available market information relative to the asset’s fair value, as compared to the asset’s carrying amount. The Company records any related impairment charge in the period in which the Company identifies such impairment.
	Loss on Retirement of Long-Term Obligations—Loss on retirement of long-term obligations primarily includes cash paid to retire debt in excess of its carrying value, non-cash charges related to the write-off of deferred financing fees, losses associated with the settlement of interest rate swaps and the write-off of any discounts or premiums. In 2014, Loss on retirement of long-term obligations includes amounts associated with the acquisition of BR Towers’ preferred equity.
	Earnings Per Common Share—Basic and Diluted—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. Dilutive common share equivalents also include the dilutive impact of the ALLTEL transaction. 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.
	Retirement Plan—The Company has a 401(k) plan covering substantially all employees who meet certain age and employment requirements. For the years ended December 31, 2014 and 2013, the Company matched 75% of the first 6% of a participant’s contributions. The Company’s matching contribution for the year ended December 31, 2012 was 50% of the first 6% of a participant’s contributions. For the years ended December 31, 2014, 2013 and 2012, the Company contributed approximately $6.5 million, $6.0 million and $4.4 million to the plan, respectively.
	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 is 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 chose to early adopt this guidance during the year ended December 31, 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 and will become effective on January 1, 2017. The standard permits the use of either the retrospective or cumulative effect transition method, and leases are not included in the scope of this standard. The Company is evaluating the impact this standard may have on its financial statements.

Prepaid_and_Other_Current_Asse

Prepaid and Other Current Assets	12 Months Ended
	Dec. 31, 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 December 31, (in thousands):
		2014		2013 (1)
	Prepaid operating ground leases	$	88,508	$	96,881
	Prepaid income tax	34,512		52,612
	Unbilled receivables	25,352		25,412
	Prepaid assets	23,848		34,243
	Value added tax and other consumption tax receivables	23,228		77,016
	Other miscellaneous current assets	59,174		61,253
	Balance as of December 31,	$	254,622	$	347,417
	__________
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Property_and_Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Property and Equipment	PROPERTY AND EQUIPMENT
	Property and equipment (including assets held under capital leases) consists of the following as of December 31, (in thousands):
		Estimated	2014			2013 (2)
		Useful  Lives (years) (1)
	Towers	Up to 20	$	8,300,387		$	7,933,917
	Equipment	15-Feb	995,667			762,738
	Buildings and improvements	Mar-32	618,889			607,540
	Land and improvements (3)	Up to 20	1,566,096			1,369,969
	Construction-in-progress		214,760			170,292
	Total		11,695,799			10,844,456
	Less accumulated depreciation and amortization		(4,068,982		)	(3,666,728		)
	Property and equipment, net		$	7,626,817		$	7,177,728
	__________
	(1) Assets on leased land are depreciated over the shorter of the estimated useful life of the asset or the term of the corresponding ground lease taking into
	consideration lease renewal options and residual value.
	(2) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
	(3) Estimated useful lives apply to land improvements only.
	Depreciation expense for the years ended December 31, 2014, 2013 and 2012 was $551.8 million, $483.6 million and $411.9 million, respectively. Property and equipment, net includes approximately $1,111.6 million and $839.0 million of capital leases, which are primarily classified as either towers or land and improvements as of December 31, 2014 and 2013, respectively.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 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, 2013		$	2,320,571			$	520,072			$	2,000			$	2,842,643
	Additions		973,328				91,249				—				1,064,577
	Effect of foreign currency translation		—				(52,418		)		—				(52,418		)
	Balance as of December 31, 2013 (1)		$	3,293,899			$	558,903			$	2,000			$	3,854,802
	Additions		48,247				168,966				—				217,213
	Effect of foreign currency translation		—				(51,280		)		—				(51,280		)
	Other (2)		—				(3,641		)		(12		)		(3,653		)
	Balance as of December 31, 2014		$	3,342,146			$	672,948			$	1,988			$	4,017,082
	__________
	(1) Balances have been revised to reflect purchase accounting measurement period adjustments.
	(2) Other represents the goodwill associated with the Company’s operations in Panama and the Company’s third-party structural analysis business. Both businesses were sold during the year ended December 31, 2014 (see note 12).
	The Company’s other intangible assets subject to amortization consist of the following:
					As of December 31, 2014												As of December 31, 2013 (1)
		Estimated Useful			Gross				Accumulated				Net Book				Gross		Accumulated			Net Book
		Lives			Carrying				Amortization				Value				Carrying		Amortization			Value
					Value												Value
		(years)			(in thousands)
	Acquired network location intangibles(2)	Up to 20			$	2,513,763			$	(901,903	)		$	1,611,860			$	2,418,153	$	(791,359	)	$	1,626,794
	Acquired customer-related intangibles	15-20			6,579,094				(1,429,572		)		5,149,522				6,017,849		(1,170,239		)	4,847,610
	Acquired licenses and other intangibles	20-Mar			43,012				(3,514		)		39,498				6,583		(2,297		)	4,286
	Economic Rights, TV Azteca	70			25,522				(12,960		)		12,562				28,783		(14,229		)	14,554
	Total				$	9,161,391			$	(2,347,949	)		$	6,813,442			$	8,471,368	$	(1,978,124	)	$	6,493,244
	Deferred financing costs, net (3)	N/A											75,889									76,875
	Other intangible assets, net												$	6,889,331								$	6,570,119
	__________
	(1) December 31, 2013 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 which 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 location intangibles and customer-related intangibles on a straight-line basis over the estimated useful lives. As of December 31, 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, is approximately 15 years. Amortization of intangible assets for the years ended December 31, 2014, 2013 and 2012 aggregated approximately $411.7 million, $282.5 million and $207.3 million, respectively. Amortization expense excludes amortization of deferred financing costs, which is included in Interest expense on the 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 next five subsequent years (in millions):
	Year Ending December 31,
	2015	$	430.8
	2016	424.4
	2017	422.7
	2018	421.8
	2019	419.9

Notes_Receivable_and_Other_Non

Notes Receivable and Other Non-current Assets	12 Months Ended
	Dec. 31, 2014
Notes Receivable And Other Long Term Assets [Abstract]
Notes Receivable and Other Non-Current Assets	NOTES RECEIVABLE AND OTHER NON-CURRENT ASSETS
	Notes receivable and other non-current assets consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Long-term prepaid ground rent	$	310,232	$	217,983
	Notes receivable	87,515		89,381
	Other miscellaneous assets	168,707		201,809
	Balance as of December 31,	$	566,454	$	509,173
	__________
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
	TV Azteca Note Receivable—In 2000, the Company loaned TV Azteca, S.A. de C.V. (“TV Azteca”), the owner of a major national television network in Mexico, $119.8 million. The loan has an interest rate of 13.11%, payable quarterly, which at the time of issuance was determined to be below market and therefore a corresponding discount was recorded. The term of the loan is seventy years; however, the loan may be prepaid by TV Azteca without penalty during the last fifty years of the agreement. The discount on the loan is being amortized to Interest income, TV Azteca, net of interest expense on the Company’s consolidated statements of operations, using the effective interest method over the seventy-year term of the loan.
	During the year ended December 31, 2013, TV Azteca made a payment of $34.4 million, which included $28.0 million of principal on the loan, related interest and a prepayment penalty of $4.9 million in accordance with the terms of the agreement. In addition during the year ended December 31, 2013, the Company recorded additional interest income of $2.7 million related to the write-off of a portion of the unamortized discount associated with the original loan. As of December 31, 2014, the outstanding balance on the loan is $91.8 million, or $82.9 million, net of discount.
	TV Azteca Economic Rights—Simultaneous with the signing of the loan agreement, the Company also entered into a seventy-year Economic Rights Agreement with TV Azteca regarding space not used by TV Azteca on approximately 190 of its broadcast towers. In exchange for the issuance of the below market interest rate loan and the annual payment of $1.5 million to TV Azteca (under the Economic Rights Agreement), the Company has the right to market and lease the unused tower space on the broadcast towers (the “Economic Rights”). TV Azteca retains title to these towers and is responsible for their operation and maintenance. The Company is entitled to 100% of the revenues generated from leases with tenants on the unused space and is responsible for any incremental operating expenses associated with those tenants.
	The term of the Economic Rights Agreement is seventy years; however, TV Azteca has the right to purchase, at fair market value, the Economic Rights from the Company at any time during the last fifty years of the agreement. Should TV Azteca elect to purchase the Economic Rights, in whole or in part, it would also be obligated to repay a proportional amount of the loan discussed above at the time of such election. The Company’s obligation to pay TV Azteca $1.5 million annually would also be reduced proportionally.
	The Company accounted for the annual payment of $1.5 million as a capital lease by initially recording an asset and a corresponding liability of approximately $18.6 million. The capital lease asset also includes the original discount on the note. The capital lease asset and original discount on the note aggregated approximately $30.2 million at the time of the transaction and represents the cost to acquire the Economic Rights. The Economic Rights asset is recorded as an intangible asset and is being amortized over the seventy-year life of the Economic Rights Agreement.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 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 accounting for the acquisitions 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 value 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 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 year ended December 31, 2014, the Company made certain measurement period adjustments related to several acquisitions consummated in 2013 and therefore retrospectively adjusted the fair value of the assets acquired and liabilities assumed in the 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 consolidated statements of operations for the year ended December 31, 2014 from the date of the 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. Sites acquired from communications service providers may never have been operated as a business and may have been utilized solely by the seller as a component of its 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 year ended December 31, 2014 is approximately $47.0 million and $37.6 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, fair value adjustments to contingent consideration and general administrative costs directly related to the transaction, and are included in Other operating expenses in the consolidated statements of operations. During the years ended December 31, 2014, 2013 and 2012, the Company recognized acquisition and merger related expenses of $27.0 million, $36.2 million and $25.6 million, respectively. In addition, during the years ended December 31, 2014 and December 31, 2013, the Company recorded $13.1 million and $1.4 million, respectively, of integration costs related to recently closed acquisitions.
	2014 Acquisitions
	BR Towers Acquisition—On November 19, 2014, the Company completed the acquisition of 100% of the equity interests of BR Towers S.A., a Brazilian telecommunications real estate company (“BR Towers”). At closing, BR Towers owned 2,504 towers and four property interests, as well as the exclusive use rights for 2,113 additional towers and 43 property interests in Brazil. The Company completed the acquisition for an estimated preliminary purchase price of approximately $568.9 million and paid approximately $61.1 million to acquire all outstanding preferred equity. In addition, the Company assumed approximately $261.1 million of BR Towers’ existing indebtedness and repaid approximately $122.1 million of principal balance subsequent to closing. The purchase price is subject to post-closing adjustments.
	Richland Acquisition—On April 3, 2014, the Company, through one of its wholly-owned subsidiaries, acquired entities holding a portfolio of 59 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 Properties LLC and other related entities (“Richland”) for a purchase price of $189.4 million, which includes approximately $6.5 million payable to the seller upon satisfaction of certain closing conditions. In addition, the Company assumed $196.5 million of Richland’s 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.  The purchase price is subject to post-closing adjustments.
	Other International Acquisitions—During the year ended December 31, 2014, the Company acquired a total of 159 communications sites and related assets in Brazil, Ghana, Mexico and Uganda, for total purchase price of $28.3 million (including value added tax of $1.2 million). The Company also acquired 299 communications sites in Mexico for a purchase price of $40.3 million (including value added tax of $5.6 million), which reflects approximately $3.4 million of net liabilities assumed. Total purchase price 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.
	Other U.S. Acquisitions—During the year ended December 31, 2014, the Company acquired a total of 184 communications sites and equipment, as well as six property interests, in the United States for total purchase price of $180.8 million (including $6.3 million for the estimated fair value of contingent consideration). The purchase price is subject to post-closing adjustments.
	The following table summarizes the preliminary allocation, unless otherwise noted, of the purchase price 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 consolidated balance sheets as of December 31, 2014.
			BR Towers			Richland				International (1)				Other U.S.
	Current assets		$	31,832		$	8,583			$	7,072			$	797
	Non-current assets		9,135			—				1,521				—
	Property and equipment		141,422			185,777				32,225				38,413
	Intangible assets (2):
	Customer-related intangible assets		495,279			169,452				20,217				89,990
	Network location intangible assets		136,233			1,700				10,729				39,470
	Other intangible assets		37,664			—				—				—
	Current liabilities		(23,930		)	(3,635		)		(863		)		(1,997		)
	Other non-current liabilities		(101,508		)	(2,922		)		(6,263		)		(1,675		)
	Net assets acquired		726,127			358,955				64,638				164,998
	Goodwill (3)		164,955			32,423				4,011				15,824
	Fair value of net assets acquired		891,082			391,378				68,649				180,822
	Debt assumed (4)		(261,136		)	(201,999		)		—				—
	Preferred stock outstanding		(61,056		)	—				—				—
	Purchase Price		$	568,890		$	189,379			$	68,649			$	180,822
	__________
	-1	The allocation of the purchase price was finalized during the year ended December 31, 2014.
	-2	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years. Other intangible assets are amortized on a straight-line basis over the life of the lease, which is a period of 11 years.
	-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 except for goodwill associated with BR Towers where goodwill is expected to be partially deductible.
	-4	BR Towers debt assumed approximated fair value at the date of acquisition and includes $11.5 million of current indebtedness. Richland debt assumed includes $196.5 million of Richland’s 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.
	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 MIP Tower Holdings LLC (“MIPT”), a private REIT and the parent company of Global Tower Partners (“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 Company sold its operations in Panama in September 2014.
	The 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 year ended December 31, 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 allocation of the purchase price was finalized during the year ended December 31, 2014. The following table summarizes the allocation of the 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).
			Final 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		10,102				10,021
	Prepaid and other current assets		40,865				22,875
	Property and equipment		910,713				996,901
	Intangible assets (3):
	Customer-related intangible assets		2,456,582				2,629,188
	Network location intangible assets		528,900				467,300
	Notes receivable and other non-current assets		68,388				4,220
	Accounts payable		(9,969		)		(9,249		)
	Accrued expenses		(42,867		)		(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		(57,965		)		(43,089		)
	Other non-current liabilities		(17,837		)		(37,326		)
	Fair value of net assets acquired		$	2,338,418			$	2,455,495
	Goodwill (5)		992,044				874,967
__________
(1) Balances are reflected as updated in the accompanying consolidated balance sheets as of December 31, 2013.
(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 a purchase price of $248.5 million.
NII Acquisition—On August 8, 2013, the Company entered into an agreement with NII Holdings, Inc. (“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 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 year ended December 31, 2014 as a result of 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 1,931 communications sites in Brazil from NII for an initial purchase price of approximately $349.0 million. The purchase price was subsequently reduced to approximately $341.4 million during the year ended December 31, 2014 as a result of post-closing adjustments. In addition, in June 2014, the Company purchased an additional 103 communications sites for a purchase price of approximately $17.7 million, which are reflected above in “2014 Acquisitions.” The Company’s right to purchase additional sites in Brazil expired on December 31, 2014.
Z-Sites Acquisition—On November 29, 2013, the Company acquired 238 communications sites from Z-Sites Locação de Imóveis Ltda for a purchase price of approximately $122.8 million. The purchase price was subsequently increased to approximately $123.9 million during the year ended December 31, 2014.
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 a 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 a purchase price of $65.6 million. 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 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 consolidated balance sheets herein.
		Axtel Mexico (1)				NII Mexico (2) (3)				NII Brazil (2)				Z-Sites (2)			Other International (2)			Other U.S. (2)
Current assets		$	—			$	59,938			$	—			$	—		$	4,863		$	1,220
Non-current assets		2,626				10,738				9,534				6,718			1,991			44
Property and equipment		86,100				143,680				109,426				26,881			44,844			23,537
Intangible assets (4):
Customer-related intangible assets		119,392				132,897				142,125				62,286			20,590			29,325
Network location intangible assets		43,031				66,069				82,111				17,350			20,727			7,935
Current liabilities		—				—				—				—			—			(454		)
Other non-current liabilities		(9,377		)		(10,478		)		(20,100		)		(2,331		)	(8,168		)	(848		)
Fair value of net assets acquired		$	241,772			$	402,844			$	323,096			$	110,904		$	84,847		$	60,759
Goodwill (5)		6,751				25,056				18,312				13,040			4,970			4,403
__________
-1	The allocation of the purchase price was finalized during the year ended December 31, 2013.
-2	The allocation of the purchase price was finalized during the year ended December 31, 2014.
-3	Current assets includes approximately $59.0 million of value added tax.
-4	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
-5	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 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 2014 acquisitions had occurred on January 1, 2013 and the 2013 acquisitions had occurred on January 1, 2012 (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.
		Year Ended December 31,
		2014				2013
Pro forma revenues		$	4,193,067			$	3,848,549
Pro forma net income attributable to American Tower Corporation common stockholders		$	770,871			$	394,253
Pro forma net income per common share amounts:
Basic net income attributable to American Tower Corporation common stockholders		$	1.95			$	1
Diluted net income attributable to American Tower Corporation common stockholders		$	1.93			$	0.99
Other Signed Acquisitions
TIM Acquisition—On November 21, 2014, the Company entered into an agreement with TIM Celular S.A. (“TIM”), a wholly-owned subsidiary of TIM Participações S.A., a publicly traded subsidiary of Telecom Italia S.p.A., to acquire two portfolios of towers in Brazil, subject to customary closing conditions. The first portfolio includes approximately 5,240 towers and the second portfolio, which was previously subject to certain preemptive acquisition rights held by third parties, includes approximately 1,240 towers. On January 16, 2015, such third parties waived their preemptive rights. At signing, total purchase price was approximately 3.0 billion BRL (approximately $1.1 billion), subject to customary adjustments. In addition, the Company may be required to pay breakup fees of an aggregate of approximately 260 million BRL, in the event that the conditions to the Company’s obligation to close have all been satisfied and the Company fails to consummate the TIM transaction. In connection with this obligation, the Company entered into letters of credit with Banco Santander in an aggregate amount of 260 million BRL.
Airtel Acquisition—On November 24, 2014, the Company and Airtel Networks Limited entered into a definitive agreement, through Bharti Airtel Limited’s subsidiary company, Bharti Airtel International (Netherlands) BV (“Airtel”), for the sale of over 4,800 of Airtel’s communications towers in Nigeria, subject to customary closing conditions and regulatory approval. At signing, the total purchase price was approximately $1.1 billion, subject to adjustments.
In February 2015, the Company signed a definitive agreement with Verizon Communications, Inc. (“Verizon”), see note 24.
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 $29.5 million, based on current exchange rates, and estimates it to be $19.7 million using a probability weighted average of the expected outcomes as of December 31, 2014. During the year ended December 31, 2014, the Company recorded an increase in fair value of $1.4 million in Other operating expenses in the accompanying 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 $0.6 million, based on current exchange rates, and estimates it to be $0.6 million using a probability weighted average of the expected outcomes as of December 31, 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 acquisition accounting 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 $4.4 million. During the year ended December 31, 2014, the Company (i) recorded a decrease in fair value of $1.7 million in Other operating expenses in the accompanying consolidated statements of operations, (ii) recorded settlements under these agreements of $3.5 million, (iii) reduced its contingent consideration liability by $0.7 million as a portion of the Company’s obligations was assumed by the buyer in conjunction with the sale of operations in Panama and (iv) recorded additional liability of $0.1 million. As a result, the Company estimates the value of potential contingent consideration payments required under these agreements to be $2.3 million using a probability weighted average of the expected outcomes as of December 31, 2014.
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. During the year ended December 31, 2014, the Company recorded $6.3 million of contingent consideration liability as part of the preliminary acquisition accounting upon closing of certain acquisitions. During the year ended December 31, 2014, the Company recorded settlements under these agreements of $0.4 million. 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 $5.9 million and estimates it to be $5.9 million using a probability weighted average of the expected outcomes as of December 31, 2014.
For more information regarding contingent consideration, see note 12.

Accrued_Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2014
Accrued Liabilities, Current [Abstract]
Accrued Expenses	ACCRUED EXPENSES
	Accrued expenses consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Accrued property and real estate taxes	$	61,206	$	54,529
	Payroll and related withholdings	57,110		50,843
	Accrued construction costs	46,024		52,446
	Accrued rent	34,074		28,456
	Other accrued expenses	219,340		234,914
	Balance as of December 31,	$	417,754	$	421,188
	__________
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

LongTerm_Obligations

Long-Term Obligations	12 Months Ended
	Dec. 31, 2014
Long-term Debt, Excluding Current Maturities [Abstract]
Long-Term Obligations	LONG-TERM OBLIGATIONS
	Outstanding amounts under the Company’s long-term obligations consist of the following as of December 31, (in thousands):
				2014				2013				Contractual Interest Rate (1)			Maturity Date (1)
		American Tower subsidiary debt:
			Secured Tower Revenue Securities, Series 2013-1A	$	500,000			$	500,000			1.551	%		March 15, 2018 (2)
			Secured Tower Revenue Securities, Series 2013-2A	1,300,000				1,300,000				3.07	%		March 15, 2023 (2)
			GTP Notes (3)	1,263,983				1,537,881				2.364% - 7.628%			Various
			BR Towers Debentures (4)	118,688				—				7.4	%		October 15, 2023
			BR Towers Credit Facility (4)	16,389				—				3.500% - 10.800%			Various
			Unison Notes (5)	203,683				205,436				5.349% - 9.522%			Various
			Mexican Loan (6)(7)	263,426				377,470				4.821	%		May 1, 2015
			South African Facility (6)(8)	75,133				88,334				9.875	%		March 31, 2020
			Colombian Credit Facility (6)(9)	83,596				—				8.36	%		April 24, 2021
			Colombian Long-Term Credit Facility	—				70,063				N/A			N/A
			Colombian Bridge Loans	—				56,058				N/A			N/A
			Colombian Loan	—				35,697				N/A			N/A
			Costa Rica Loan	—				32,600				N/A			N/A
			Shareholder loans (10)	137,655				225,253				Various			Various
		Total American Tower subsidiary debt		3,962,553				4,428,792
		American Tower Corporation debt:
			2013 Credit Facility (6)	—				1,853,000				1.41	%		June 28, 2018
			2013 Term Loan (6)	1,500,000				1,500,000				1.41	%		January 3, 2019
			2014 Credit Facility (6)(11)	1,100,000				88,000				1.41	%		January 31, 2020
			4.625% Notes (12)	599,958				599,794				4.625	%		April 1, 2015
			7.00% Notes	500,000				500,000				7	%		October 15, 2017
			4.50% Notes	999,631				999,520				4.5	%		January 15, 2018
			3.40% Notes	1,005,509				749,373				3.4	%		February 15, 2019
			7.25% Notes	297,260				296,748				7.25	%		May 15, 2019
			5.05% Notes	699,496				699,413				5.05	%		September 1, 2020
			3.450% Notes	646,394				—				3.45	%		September 15, 2021
			5.90% Notes	499,474				499,414				5.9	%		November 1, 2021
			4.70% Notes	698,987				698,871				4.7	%		March 15, 2022
			3.50% Notes	993,230				992,520				3.5	%		January 31, 2023
			5.00% Notes	1,010,834				499,455				5	%		February 15, 2024
		Total American Tower Corporation debt		10,550,773				9,976,108
	Other debt, including capital lease obligations			95,382				73,378
			Total	14,608,708				14,478,278
	Less current portion of long-term obligations			(897,624		)		(70,132		)
			Long-term obligations	$	13,711,084			$	14,408,146
	__________
	(1) Represents the interest rate and maturity date as of December 31, 2014 and does not reflect the impact of interest rate swap agreements.
	(2) Represents anticipated repayment date.
	(3) Includes approximately $26.9 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments for debt assumed upon the acquisition of MIPT.
	(4) Denominated in Brazilian Real (“BRL”). As of December 31, 2014, the aggregate principal amount outstanding under the BR Towers Debentures and the BR Towers Credit Facility is 315.3 million BRL and 43.5 million BRL respectively. A portion of the debt accrues interest at a variable rate.
	(5) Includes approximately $7.7 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments recognized upon the acquisition of Unison Holdings, LLC and Unison Site Management II, L.L.C. (collectively, “Unison”).
	(6) Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.
	(7) Denominated in Mexican Pesos (“MXN”). As of December 31, 2014, the aggregate principal amount outstanding under the Mexican Loan is 3.9 billion MXN.
	(8) Denominated in South African Rand (“ZAR”). As of December 31, 2014, the aggregate principal amount outstanding under the South African Facility is
	869.3 million ZAR.
	(9) Denominated in Colombian Pesos (“COP”). As of December 31, 2014, the aggregate principal amount outstanding under the Colombian Credit Facility is 200.0 billion COP.
	(10) Reflects balances owed to the Company’s joint venture partners in Ghana and Uganda. The Ghana loan is denominated in Ghanaian Cedi (“GHS”) and the Uganda loan is denominated in USD.
	(11) On September 19, 2014, the Company amended and restated its $1.0 billion senior unsecured revolving credit facility as described below.
	(12) On February 11, 2015, the Company redeemed all of the outstanding 4.625% senior notes due 2015. See note 24.
	American Tower Subsidiary Debt
	Secured Tower Revenue Securities, Series 2013-1A and Series 2013-2A—In March 2013, the Company completed a securitization transaction (the “Securitization”) involving assets related to 5,195 wireless and broadcast communications towers (the “Secured Towers”) owned by two special purpose subsidiaries of the Company, through a private offering of $1.8 billion of the Securities. The net proceeds of the transaction were $1.78 billion. The Securities were issued by American Tower Trust I (the “Trust”), a trust established by American Tower Depositor Sub, LLC, an indirect wholly owned special purpose subsidiary of the Company. The assets of the Trust consist of a nonrecourse loan (the “Loan”) to American Tower Asset Sub, LLC and American Tower Asset Sub II, LLC (the “Borrowers”), pursuant to a First Amended and Restated Loan and Security Agreement dated as of March 15, 2013 (the “Loan Agreement”). The Borrowers are special purpose entities formed solely for the purpose of holding the Secured Towers subject to a securitization.
	The Securities were issued in two separate series of the same class pursuant to a First Amended and Restated Trust and Servicing Agreement (the “Trust Agreement”), with terms identical to the Loan. The effective weighted average life and interest rate of the Securities is 8.6 years and 2.648%, respectively, as of the date of issuance.
	Amounts due under the Loan will be paid by the Borrowers from the cash flows generated by the Secured Towers. These funds in turn will be used by or on behalf of the Trust to service the payment of interest on the Securities and for any other payments required by the Loan Agreement or Trust Agreement. The Borrowers are required to make monthly payments of interest on the Loan. Subject to certain limited exceptions described below, no payments of principal will be required to be made prior to March 15, 2018, which is the anticipated repayment date for the component of the Loan associated with the Series 2013-1A Securities. On a monthly basis, after payment of all required amounts under the Loan Agreement and Trust Agreement, the excess cash flows generated from the operation of the Secured Towers are released to the Borrowers, and can then be distributed to, and used by, the Company. However, if the debt service coverage ratio (the “DSCR”), generally defined as the net cash flow divided by the amount of interest, servicing fees and trustee fees that the Borrowers will be required to pay over the succeeding twelve months on the principal amount of the Loan, as of the last day of any calendar quarter prior to the applicable anticipated repayment date, were equal to or below 1.30x (the “Cash Trap DSCR”) for such quarter, and the DSCR continues to be equal to or below the Cash Trap DSCR for two consecutive calendar quarters, then all cash flow in excess of amounts required to make debt service payments, to fund required reserves, to pay management fees and budgeted operating expenses and to make other payments required under the loan documents, referred to as excess cash flow, will be deposited into a reserve account instead of being released to the Borrowers. The funds in the reserve account will not be released to the Borrowers unless the DSCR exceeds the Cash Trap DSCR for two consecutive calendar quarters. An “amortization period” commences if (i) as of the end of any calendar quarter the DSCR equals or falls below 1.15x (the “Minimum DSCR”) for such calendar quarter and such amortization period will continue to exist until the DSCR exceeds the Minimum DSCR for two consecutive calendar quarters or (ii) on the anticipated repayment date the component of the Loan corresponding to the applicable subclass of the Securities has not been repaid in full, provided that such amortization period shall apply with respect to such component that has not been repaid in full. During an amortization period all excess cash flow and any amounts then in the reserve account because the Cash Trap DSCR was not met would be applied to payment of the principal on the Loan.
	The Borrowers may prepay the Loan in whole or in part at any time provided it is accompanied by applicable prepayment consideration. If the prepayment occurs within twelve months of the anticipated repayment date for the Series 2013-1A Securities or eighteen months of the anticipated repayment date for the Series 2013-2A Securities, no prepayment consideration is due. The entire unpaid principal balance of the component of the Loan related to the Series 2013-1A Securities and the Series 2013-2A Securities has a final maturity date of March 2043 and March 2048, respectively. The Loan may be defeased in whole at any time prior to the anticipated repayment date for any component of the Loan then outstanding.
	The Loan is secured by (1) mortgages, deeds of trust and deeds to secure debt on substantially all of the Secured Towers, (2) a pledge of the Borrowers’ operating cash flows from the Secured Towers, (3) a security interest in substantially all of the Borrowers’ personal property and fixtures and (4) the Borrowers’ rights under the tenant leases and the management agreement entered into in connection with the Securitization. American Tower Holding Sub, LLC, whose only material assets are its equity interests in each of the Borrowers, and American Tower Guarantor Sub, LLC, whose only material asset is its equity interest in American Tower Holding Sub, LLC, each have guaranteed repayment of the Loan and pledged their equity interests in their respective subsidiary or subsidiaries as security for such payment obligations. American Tower Guarantor Sub, LLC, American Tower Holding Sub, LLC, the Depositor and the Borrowers each were formed as special purpose entities solely for purposes of entering a securitization transaction, and the assets and credit of these entities are not available to satisfy the debts and other obligations of the Company or any other person, except as set forth in the Loan Agreement.
	The Loan Agreement includes operating covenants and other restrictions customary for loans subject to rated securitizations. Among other things, the Borrowers are prohibited from incurring other indebtedness for borrowed money or further encumbering their assets subject to customary carve-outs for ordinary course trade payables and permitted encumbrances (as defined in the Loan Agreement). The organizational documents of the Borrowers contain provisions consistent with rating agency securitization criteria for special purpose entities, including the requirement that the Borrowers maintain at least two independent directors. The Loan Agreement also contains certain covenants that require the Borrowers to provide the trustee with regular financial reports and operating budgets, promptly notify the trustee of events of default and material breaches under the Loan Agreement and other agreements related to the Secured Towers, and allow the trustee reasonable access to the Secured Towers, including the right to conduct site investigations.
	A failure to comply with the covenants in the Loan Agreement could prevent the Borrowers from taking certain actions with respect to the Secured Towers, and could prevent the Borrowers from distributing any excess cash from the operation of the Secured Towers to the Company. If the Borrowers were to default on the Loan, the servicer could seek to foreclose upon or otherwise convert the ownership of the Secured Towers, in which case the Company could lose the Secured Towers and the revenue associated with those assets.
	Under the Loan Agreement, the Borrowers are required to maintain reserve accounts, including for ground rents, real estate and personal property taxes and insurance premiums, and to reserve a portion of advance rents from tenants on the Secured Towers. Based on the terms of the Loan Agreement, all rental cash receipts received for each month are reserved for the succeeding month and held in an account controlled by the trustee and then released. The $118.8 million held in the reserve accounts as of December 31, 2014 was classified as Restricted cash on the Company’s accompanying consolidated balance sheet.
	GTP Notes—In connection with the acquisition of MIPT, the Company assumed approximately $1.49 billion principal amount of existing indebtedness issued by certain subsidiaries of GTP in several securitization transactions. GTP Acquisition Partners I, LLC (“GTP Partners”) issued the Series 2011-1 notes, Series 2011-2 notes and Series 2013-1 notes, and GTP Cellular Sites, LLC (“GTP Cellular Sites,” and together with GTP Partners, the “GTP Issuers”) issued the Series 2012-1 notes and Series 2012-2 notes.
	In August 2014, the Company repaid in full the aggregate principal amount outstanding of $250.0 million under the Series 2010-1 Class C Notes and the Series 2010-1 Class F Notes issued by GTP Towers Issuer, LLC (together, the “Series 2010-1 Notes”) and wrote-off the unamortized premium associated with the fair value adjustment. As a result, the Company recorded a gain on retirement of long-term obligations in the accompanying consolidated statements of operations of $3.0 million.
The following table sets forth certain terms of the GTP Notes:
GTP Notes	Issue Date	Original Principal Amount	Interest Rate		Anticipated Repayment Date	Final Maturity Date
		(in thousands)
Series 2011-1 Class C notes	March 11, 2011	$70,000	3.967	%	June 15, 2016	June 15, 2041
Series 2011-2 Class C notes	July 7, 2011	$490,000	4.347	%	June 15, 2016	June 15, 2041
Series 2011-2 Class F notes	July 7, 2011	$155,000	7.628	%	June 15, 2016	June 15, 2041
Series 2012-1 Class A notes (1)	February 28, 2012	$100,000	3.721	%	March 15, 2017	March 15, 2042
Series 2012-2 Class A notes (1)	February 28, 2012	$114,000	4.336	%	March 15, 2019	March 15, 2042
Series 2012-2 Class B notes	February 28, 2012	$41,000	6.413	%	March 15, 2019	March 15, 2042
Series 2012-2 Class C notes	February 28, 2012	$27,000	7.358	%	March 15, 2019	March 15, 2042
Series 2013-1 Class C notes	April 24, 2013	$190,000	2.364	%	May 15, 2018	May 15, 2043
Series 2013-1 Class F notes	April 24, 2013	$55,000	4.704	%	May 15, 2018	May 15, 2043
__________
(1) Does not reflect MIPT’s repayment of approximately $1.4 million aggregate principal amount prior to the date of acquisition and the Company’s repayment of approximately $3.5 million aggregate principal amount after the date of acquisition in accordance with the repayment schedules.
The GTP Notes may be prepaid in whole or in part at any time beginning two years after the date of issuance, provided such payment is accompanied by applicable prepayment consideration. If the prepayment occurs within one year of the anticipated repayment date, no prepayment consideration is due.
As of December 31, 2014, the GTP Notes are secured by, among other things, an aggregate of 2,845 sites and 1,035 property interests owned by subsidiaries of the GTP Issuers and other related assets (the “GTP Secured Sites”).
Cash flows generated by the GTP Secured Sites will be used to pay amounts due under the applicable series of GTP Notes, including the payment of interest on the applicable series of GTP Notes and for any other payments required by the indentures governing the GTP Notes (the “GTP Indentures”).
On a monthly basis, after payment of all required amounts under the GTP Indentures, the excess cash flows generated from the operation of the GTP Secured Sites are released to the GTP Issuers, and can then be distributed to, and used by, the Company. The GTP Issuers must maintain a specified ratio with respect to their DSCR, calculated as the ratio of the net cash flow (as defined in the applicable GTP Indentures) to the amount of interest required to be paid over the succeeding twelve months on the principal amount of the GTP Notes that will be outstanding on the payment date following such date of determination, plus the amounts payable for trustee and servicing fees. If the DSCR with respect to any series of GTP Notes issued by GTP Partners is equal to or below the Cash Trap DSCR at the end of any calendar quarter and it continues for two consecutive calendar quarters, or if the DSCR with respect to any series of GTP Notes issued by GTP Cellular Sites is equal to or below the Cash Trap DSCR at the end of any calendar month and it continues for two consecutive calendar months, then all cash flow in excess of amounts required to make debt service payments, fund required reserves, pay management fees and budgeted operating expenses and make other payments required with respect to such series of GTP Notes under the GTP Indentures, will be deposited into reserve accounts instead of being released to the GTP Issuers. The funds in the reserve accounts will not be released to GTP Partners for distribution to the Company unless the DSCR with respect to such series of GTP Notes exceeds the Cash Trap DSCR for two consecutive calendar quarters. Likewise, the funds in the reserve account will not be released to GTP Cellular Sites for distribution to the Company unless the DSCR with respect to such series of GTP Notes exceeds the Cash Trap DSCR for two consecutive calendar months.
Additionally, an “amortization period” commences as of the end of any calendar quarter with respect to the series of GTP Notes issued by GTP Partners, and as of the end of any calendar month with respect to the series of GTP Notes issued by GTP Cellular Sites, if the DSCR of such series equals or falls below the Minimum DSCR. The “amortization period” will continue to exist until the end of any calendar quarter with respect to the series of GTP Notes issued by GTP Partners, for which the DSCR exceeds the Minimum DSCR for two consecutive calendar quarters. With respect to the series of GTP Notes issued by GTP Cellular Sites, the “amortization period” will continue to exist until the end of any calendar month for which the DSCR exceeds the Minimum DSCR for two consecutive calendar months. During an amortization period all excess cash flow and any amounts then in the reserve accounts because the Cash Trap DSCR was not met would be applied to payment of the principal of the applicable series of GTP Notes.
The GTP Indentures include operating covenants and other restrictions customary for note offerings subject to rated securitizations. Among other things, the GTP Issuers are prohibited from incurring other indebtedness for borrowed money or further encumbering their assets subject to customary exceptions for ordinary course trade payables and permitted encumbrances (as defined in the GTP Indentures). The GTP Indentures also contain certain covenants that require the GTP Issuers to provide the trustee with regular financial reports, operating budgets and budgets for capital improvements not included in annual financial statements in accordance with GAAP, promptly notify the trustee of events of default and material breaches under the GTP Indentures and other agreements related to the GTP Secured Sites, and allow the trustee reasonable access to the GTP Secured Sites, including the right to conduct site investigations.
A failure to comply with the covenants in the GTP Indentures could prevent the GTP Issuers from taking certain actions with respect to the GTP Secured Sites and could prevent the GTP Issuers from distributing excess cash flow to the Company. In addition, upon occurrence and during an event of default, the trustee may, in its discretion or at direction of holders of more than 50% of the aggregate outstanding principal of any series of GTP Notes, declare such series of GTP Notes immediately due and payable, in which case any excess cash flow would need to be used to pay holders of such GTP Notes. Furthermore, if the GTP Issuers were to default on a series of the GTP Notes, the trustee may demand, collect, take possession of, receive, settle, compromise, adjust, sue for, foreclose or realize upon all or any portion of the GTP Secured Sites securing such series, in which case the GTP Issuers could lose the GTP Secured Sites and the revenue associated with those assets.
Under the GTP Indentures, the GTP Issuers are required to maintain reserve accounts, including for amounts received or due from tenants related to future periods, property taxes, insurance, ground rents, certain expenses and debt service. The $20.9 million held in the reserve accounts as of December 31, 2014 is classified as Restricted cash on the accompanying consolidated balance sheets.
BR Towers Debt—In connection with the acquisition of BR Towers, the Company assumed approximately 671.5 million BRL (approximately $261.1 million based on exchange rates at the date of closing) aggregate principal amount of existing indebtedness consisting of (i) 323.4 million of BRL denominated privately issued simple debentures (“BR Towers Private Debentures”) (with an original principal amount of 330.0 million BRL), (ii) 313.1 million BRL of denominated publicly issued simple debentures (“BR Towers Debentures”) (with an original principal amount of 300.0 million BRL) issued by a subsidiary of BR Towers (the “BRT Issuer”), and (iii) a BRL denominated credit facility with Banco Nacional de Desenvolvimento Economico e Social, which allows a subsidiary of BR Towers (the “BRT Borrower”) to borrow up to 48.1 million BRL through an intermediary bank (the “BR Towers Credit Facility”).
On December 11, 2014, the Company repaid all amounts outstanding under the BR Towers Private Debentures, which included a prepayment penalty of 3.2 million BRL (approximately $1.2 million on the date of repayment).
The BR Towers Debentures were issued on October 15, 2013, and have a maturity date of October 15, 2023. The BR Towers Debentures bear interest at a rate of 7.40%. The aggregate principal amount of the BR Towers Debentures may be adjusted periodically relative to changes in the National Extended Consumer Price Index. Any such increase in the principal amount will be capitalized in a manner consistent with the agreement governing the BR Towers Debentures (the “Debenture Agreement”). Payments of principal and interest are made quarterly, beginning on January 15, 2014, in accordance with the amortization schedule set forth in the agreement governing the BR Towers Debentures (the “Debenture Agreement”).
The Company may redeem the BR Towers Debentures beginning on October 15, 2018 at the then outstanding principal amount plus a surcharge, calculated in accordance with the Debenture Agreement, and all accrued and unpaid interest thereon. As of December 31, 2014, 315.3 million BRL (approximately $118.7 million) aggregate principal amount is outstanding under the BR Towers Debentures.
The BR Towers Debentures are secured by (i) 100% of the shares of the BRT Issuer and (ii) all proceeds and rights from the issuance of the BR Towers Debentures, including amounts in a Resource Account (as defined in the applicable agreement). The Debenture Agreement includes contractual covenants and other restrictions customary for public debentures. Among other things, the Debenture Agreement requires that (i) the BRT Issuer maintain a debt service coverage ratio of at least 1.10, (ii) the risk rating of the BR Towers Debentures not be downgraded by two or more notches, (iii) the BRT Issuer meet certain conditions to distribute dividends or interest on the issuer’s own capital, (iv) the issuer not incur additional indebtedness in an aggregate amount greater than 5.0 million BRL (which amount is subject to adjustment as set forth in the agreement) and (v) the issuer maintain a leverage index (as defined in the Debenture Agreement) of at least 30%.
The BR Towers Credit Facility consists of three sublimits, the material terms of which are as follows:
		Maximum Borrowing Amount		Maturity Date		Interest Rate as of
		(BRL, in millions)				31-Dec-14
Sublimit A		20.2 BRL ($7.6 USD)		15-Jul-20		10.8	%	-1
Sublimit B		27.6 BRL ($10.4 USD)		15-Jan-22		3.5	%
Sublimit C		0.2 BRL ($0.1 USD)		15-Jul-20		5.9	%	-1
(1) Sublimit A and Sublimit C accrue interest at a per annum rate equal to 4.80% plus 1.00% and 0.90%, respectively, above the Long-Term Interest Rates disclosed by the Central Bank of Brazil (the “LTIR”). If the LTIR exceeds 6.00%, the amount of interest payable on the portion of the LTIR exceeding 6.00% will be capitalized in a manner pursuant to the terms of the loan agreement.
As of December 31, 2014, 43.5 million BRL (approximately $16.4 million) is outstanding under the BR Towers Credit Facility and the BRT Borrower maintains the ability to draw down the remaining 4.6 million BRL (approximately $1.7 million) until June 26, 2015. The BRT Borrower is required to pay a fee on any amount that remains undrawn at such date, which fee will be equal to a monthly charge of 0.1% of the undrawn portion of the loan, calculated from January 15, 2014.
Any outstanding principal and accrued but unpaid interest on the BR Towers Credit Facility will be due and payable in full at maturity. The BR Towers Credit Facility may be prepaid in whole or in part, subject to certain limitations and prepayment consideration, at any time. Interest on the BR Towers Credit Facility is payable quarterly until the first amortization date, August 15, 2015, after which time principal and interest payments will be made on a monthly basis.
The BR Towers Credit Facility is secured by the conditional assignment of receivables. The loan agreements include certain reporting, information, financial ratios and operating covenants. Failure to comply with certain of the financial and operating covenants would constitute a default, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable.
Unison Notes—In connection with the acquisition of Unison, the Company assumed $196.0 million of existing indebtedness with an acquisition date fair value of $209.3 million under the Unison Notes issued by Unison Ground Lease Funding, LLC (the “Unison Issuer”) in a securitization transaction (the “Unison Securitization”). The three classes of Unison Notes bear interest at rates of 5.349%, 6.392% and 9.522%, respectively, with anticipated repayment dates of April 15, 2017, April 15, 2020 and April 15, 2020, respectively, and a final maturity date of April 15, 2040.
The Unison Notes are secured by, among other things, liens on approximately 1,517 real property interests owned by two special purpose subsidiaries of the Unison Issuer (together with the Unison Issuer, the “Unison Obligors”) and other related assets. The indenture for the Unison Notes (the “Unison Indenture”) includes certain financial ratios and operating covenants and other restrictions customary for notes subject to rated securitizations. Among other things, the Unison Obligors are restricted from incurring other indebtedness or further encumbering their assets.
Under the terms of the Unison Indenture, the Unison Notes will be paid from the cash flows generated by the communications sites subject to the Unison Securitization. The Unison Issuer is required to make monthly payments of interest to holders of the Unison Notes. On a monthly basis, cash flows in excess of amounts needed to make debt service payments and other payments required under the Unison Indenture are to be distributed to the Unison Issuer, which may then be distributed to, and used by, the Company. The Unison Issuer may prepay the Unison Notes in whole or in part at any time, provided such payment is accompanied by applicable prepayment consideration. If the prepayment occurs within six months of the anticipated repayment date, no prepayment consideration is due.
A failure to comply with the covenants in the Unison Indenture could prevent the Unison Obligors from taking certain actions with respect to the property interests subject to the Unison Securitization and a failure to meet certain financial ratio tests could prevent excess cash flow from being distributed to the Unison Issuer. In addition, if the Unison Issuer were to default on the Unison Notes, the trustee could seek to foreclose upon the property interests subject to the Unison Securitization, in which case the Company could lose ownership of the property interests and the revenue associated with those property interests.
Mexican Loan—In connection with the acquisition of towers in Mexico from NII during the fourth quarter of 2013, one of the Company’s Mexican subsidiaries entered into a 5.2 billion 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 further draw under the Mexican Loan expired in February 2014. The Mexican Loan bears interest at a margin over the Equilibrium Interbank Interest Rate (“TIIE”). During the year ended December 31, 2014, the Mexican subsidiary repaid 1.1 billion MXN (approximately $80.4 million on the date of repayment) of the outstanding indebtedness using cash on hand. As of December 31, 2014, the current margin over TIIE is 1.50%.
Shareholder Loans—In connection with the establishment of certain of the Company’s joint ventures and related acquisitions of communications sites in Ghana and Uganda, the Company’s majority owned subsidiaries entered into shareholder loan agreements, as the borrower, and with wholly owned subsidiaries of the Company and of the Company’s joint venture partners, as lenders. The portions of the loans made by the Company’s wholly owned subsidiaries are eliminated in consolidation and the portions of the loans made by each of the Company’s joint venture partner’s wholly owned subsidiary are reported as outstanding debt of the Company. Outstanding amounts under each of the Company’s shareholder loans consist of the following as of December 31, (in thousands):
	2014			2013			Contractual Interest Rate			Maturity Date
2014 Ghana Loan(1)(2)	68,651			—			21.87	%		December 31, 2019
Uganda Loan(3)(4)	69,004			66,926			5.842	%		June 29, 2019
Ghana Loan(2)	—			158,327			N/A			N/A
(1)     Denominated in GHS. As of December 31, 2014, the aggregate principal amount outstanding under the 2014 Ghana Loan is 220.9 million GHS.
(2)     During the year ended December 31, 2014, the joint venture in Ghana converted $175.2 million of existing notes under the U.S. Dollar-denominated
Ghana Loan into a new 220.9 million GHS (approximately $68.7 million) denominated shareholder loan. The remaining balance of the Ghana Loan was
converted into equity of the respective holders.
(3)     Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.
(4)     Includes approximately $2.1 million of capitalized accrued interest pursuant to the terms of the loan agreement.
South African Facility—One of the Company’s South African subsidiaries (the “SA Borrower”) entered into a 1.2 billion ZAR denominated credit facility (the “South African Facility”) in November 2011. In September 2013, the SA Borrower’s ability to draw on the South African Facility expired.
Principal and interest are payable quarterly in arrears with principal due in accordance with the repayment schedule included in the loan agreement. Outstanding principal and accrued but unpaid interest will be due and payable in full at maturity. The South African Facility may be prepaid in whole or in part without prepayment consideration.
The South African Facility is secured by, among other things, liens on towers owned by the SA Borrower. The loan agreement contains certain reporting, information, financial ratios and operating covenants. Failure to comply with certain of the financial and operating covenants would constitute a default, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable. Under the terms of the South African Facility, interest is payable quarterly at a rate generally equal to 3.75% per annum, plus the three month Johannesburg Interbank Agreed Rate (“JIBAR”). The loan agreement requires that the SA Borrower manage exposure to variability in interest rates on at least fifty percent of the amounts outstanding under the South African Facility. After giving effect to the interest rate swap agreements, the facility accrues interest at a weighted average rate of 10.34%.
Colombian Credit Facility—On October 14, 2014, one of the Company’s Colombian subsidiaries (“ATC Sitios”) entered into a loan agreement for a new 200.0 billion COP (approximately $96.8 million at the date of borrowing) denominated long-term credit facility (the “Colombian Credit Facility”), which it used, together with cash on hand, to repay a previously existing COP denominated long-term credit facility entered into in October 2012 (the “Colombian Long-Term Credit Facility”), as well as to repay six COP denominated bridge loans on October 24, 2014.
Any outstanding principal and accrued but unpaid interest will be due and payable in full at maturity. The Colombian Credit Facility may be prepaid in whole or in part, subject to certain limitations and prepayment consideration, at any time.
Principal and interest are payable quarterly in arrears with principal due in accordance with the repayment schedule included in the loan agreement. Interest accrues at a per annum rate equal to 4.00% above the three-month Inter-bank Rate (“IBR”) in effect at the beginning of each Interest Period (as defined in the loan agreement). The loan agreement also requires that ATC Sitios manage exposure to variability in interest rates on certain of the amounts outstanding under the Colombian Credit Facility. As of December 31, 2014, the interest rate, after giving effect to the interest rate swap agreements, is 9.05%.
The Colombian Credit Facility is secured by, among other things, liens on towers owned by ATC Sitios. The loan agreement contains certain reporting, information, financial ratios and operating covenants. Failure to comply with certain of the financial and operating covenants would constitute a default, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable.
Colombian Long-Term Credit Facility—In October 2012, ATC Sitios entered into the Colombian Long-Term Credit Facility, which it used to refinance the previously existing COP denominated short-term credit facility. On October 24, 2014, the Company repaid the Colombian Long-Term Credit Facility using proceeds from the Colombian Credit Facility and cash on hand.
Colombian Bridge Loans—In connection with the acquisition of communications sites in Colombia, one of the Company’s Colombian subsidiaries entered into six COP denominated bridge loans, which were repaid in full on October 24, 2014 using proceeds from the Colombian Credit Facility and cash on hand.
Colombian Loan—In connection with the establishment of the Company’s joint venture with 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. Pursuant to the loan agreement, accrued interest was periodically capitalized and added to the principal amount outstanding. The portion of the Colombian Loan made by the ATC Colombian Subsidiary was eliminated in consolidation, and the portion of the Colombian Loan made by the Millicom Subsidiary was reported as outstanding debt of the Company. During the year ended December 31, 2014, the joint venture borrowed an additional $3.0 million under the Colombian Loan, which was subsequently converted from debt to equity. 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 are eliminated in consolidation as of December 31, 2014.
Costa Rica Loan—In connection with the 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.
Richland Notes—In connection with its acquisition of entities holding a portfolio of communications sites from Richland, 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 consolidated statements of operations of $1.3 million.
Indian Working Capital Facility—In April 2013, one of the Company’s Indian subsidiaries (“ATC India”) entered into a working capital facility agreement (the “Indian Working Capital Facility”), which allows ATC India to borrow an amount not to exceed the Indian Rupee (“INR”) equivalent of $10.0 million. Any advances made pursuant to the Indian Working Capital Facility will be payable on the earlier of demand or six months following the borrowing date and the interest rate will be determined at the time of advance by the bank. ATC India has no amounts outstanding under the Indian Working Capital Facility. ATC India maintains the ability to draw down and repay amounts under the Indian Working Capital Facility in the ordinary course.
American Tower Corporation Debt
2013 Credit Facility—In June 2013, the Company entered into a $1.5 billion multi-currency senior unsecured revolving credit facility, which was subsequently increased to $2.0 billion (the “2013 Credit Facility”), which includes a $1.0 billion sublimit for multicurrency borrowings, a $200.0 million sublimit for letters of credit, a $50.0 million sublimit for swingline loans and 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 2013 Credit Facility has a term of five years and includes two optional one-year renewal periods. Any outstanding principal and accrued but unpaid interest will be due and payable in full at final maturity. 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 Company has the option of choosing either a defined base rate or LIBOR as the applicable base rate for borrowings under the 2013 Credit Facility. The interest rate ranges between 1.125% to 2.000% above LIBOR for LIBOR based borrowings or between 0.125% to 1.000% above the defined base rate for base rate borrowings, in each case based upon the Company’s debt ratings. A quarterly commitment fee on the undrawn portion of the 2013 Credit Facility is required, ranging from 0.125% to 0.400% per annum, based upon the Company’s debt ratings. The current margin over LIBOR that the Company would incur on borrowings (should it choose LIBOR Advances) is 1.250%. The current commitment fee on the undrawn portion of the new credit facility is 0.150%.
The loan agreement contains certain reporting, information, financial and operating covenants and other restrictions (including limitations on additional debt, guaranties, sales of assets and liens) with which the Company must comply. Any failure to comply with the financial and operating covenants of the loan agreement would not only prevent the Company from being able to borrow additional funds, but would constitute a default, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable.
On September 19, 2014, the Company entered into an amendment agreement with respect to the 2013 Credit Facility, which (i) amended the limitation on indebtedness of, and guaranteed by, the Company’s subsidiaries to the greater of (x) $800.0 million and (y) 50% of Adjusted EBITDA (as defined in the 2013 Credit Facility) on a consolidated basis as of the last day of the most recently completed fiscal quarter and (ii) permitted indebtedness owed by certain of the Company’s subsidiaries to its joint venture partners.
During the year ended December 31, 2014, the Company borrowed $912.0 million and repaid an aggregate of $2.8 billion of revolving indebtedness under the 2013 Credit Facility. As of December 31, 2014, the Company has approximately $3.2 million of undrawn letters of credit under the 2013 Credit Facility and maintains the ability to draw down and repay amounts under the 2013 Credit Facility in the ordinary course.
In February 2015, the Company entered into amendments to the 2013 Credit Facility, see note 24.
Short-Term Credit Facility—In September 2013, the Company entered into a $1.0 billion senior unsecured revolving credit facility (the “Short-Term Credit Facility”), which matured on September 19, 2014. The Short-Term Credit Facility was undrawn at the time of maturity.
2013 Term Loan—In October 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.
Any outstanding principal and accrued but unpaid interest will be due and payable in full at maturity. The 2013 Term Loan may be paid prior to maturity in whole or in part at the Company’s option without penalty or premium. The Company has the option of choosing either a defined base rate or LIBOR as the applicable base rate. The interest rate ranges between 1.125% to 2.250% above LIBOR or between 0.125% to 1.250% above the defined base rate, in each case based upon the Company’s debt ratings. The current margin over LIBOR is 1.250%.
The loan agreement contains certain reporting, information, financial and operating covenants and other restrictions (including limitations on additional debt, guaranties, sales of assets and liens) with which the Company must comply. Any failure to comply with the financial and operating covenants of the loan agreement would constitute a default, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable.
On September 19, 2014, the Company entered into an amendment agreement with respect to the 2013 Term Loan, which (i) amended the limitation on indebtedness of, and guaranteed by, the Company’s subsidiaries to the greater of (x) $800.0 million and (y) 50% of Adjusted EBITDA (as defined in the 2013 Term Loan) on a consolidated basis as of the last day of the most recently completed fiscal quarter and (ii) permitted indebtedness owed by certain of the Company’s subsidiaries to its joint venture partners.
In February 2015, the Company entered into amendments to the 2013 Term Loan, see note 24.
2014 Credit Facility—On September 19, 2014, the Company entered into an amendment and restatement of the $1.0 billion senior unsecured revolving credit facility entered into in January 2012 (as amended, the “2014 Credit Facility”), which, among other things, (i) increased the commitments thereunder to $1.5 billion, including a $50.0 million sublimit for swingline loans and a $200.0 million sublimit for letters of credit, (ii) extended the maturity date to January 31, 2020, including up to two optional renewal periods, (iii) amended the limitation on indebtedness of, and guaranteed by, the Company’s subsidiaries to the greater of (x) $800.0 million and (y) 50% of Adjusted EBITDA (as defined in the 2014 Credit Facility) on a consolidated basis as of the last day of the most recently completed fiscal quarter, (iv) permitted indebtedness owed by certain of the Company’s subsidiaries to its joint venture partners and (v) added an expansion feature, which allows the Company to request up to an aggregate of $500.0 million in additional commitments upon satisfaction of certain conditions.
Amounts borrowed under the 2014 Credit Facility will bear interest, at the Company’s option, at a margin above LIBOR or the Base Rate. For LIBOR based borrowings, interest rates will range from 1.125% to 2.000% above LIBOR. For Base Rate borrowings, interest rates will range from 0.125% to 1.000% above the Base Rate. In each case, the applicable margin is based upon the Company’s debt ratings. In addition, the 2014 Credit Facility requires a quarterly commitment fee on the undrawn portion of the commitments ranging from 0.125% to 0.400% per annum, based upon the Company’s debt ratings. 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 commitments is 0.150%. The 2014 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 loan agreement contains certain reporting, information, financial and operating covenants and other restrictions (including limitations on additional debt, guaranties, sales of assets and liens) with which the Company must comply. Any failure to comply with the financial and operating covenants of the loan agreement would not only prevent the Company from being able to borrow additional funds, but would constitute a default, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable.
During the year ended December 31, 2014, the Company borrowed $1.3 billion and repaid an aggregate of $263.0 million of revolving indebtedness under the 2014 Credit Facility. As of December 31, 2014, the Company has approximately $8.0 million of undrawn letters of credit under the 2014 Credit Facility and maintains the ability to draw down and repay amounts under the 2014 Credit Facility in the ordinary course.
In February 2015, the Company entered into amendments to the 2014 Credit Facility, see note 24.
Outstanding Senior Notes
3.40% Senior Notes and 5.00% 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 2014 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.
3.450% Senior Notes Offering—On August 7, 2014, the Company completed a registered public offering of its 3.450% senior unsecured notes due 2021 (the “3.450% Notes”), in an aggregate principal amount of $650.0 million. The net proceeds from the offering were approximately $641.1 million, after deducting commissions and estimated expenses. The Company used the proceeds to repay existing indebtedness under the 2013 Credit Facility.
The 3.450% Notes mature on September 15, 2021 and bear interest at a rate of 3.450% per annum. Accrued and unpaid interest on the 3.450% Notes is payable in U.S. Dollars semi-annually in arrears on March 15 and September 15 of each year, beginning on March 15, 2015. Interest on the 3.450% Notes accrues from August 7, 2014 and is computed on the basis of a 360-day year comprised of twelve 30-day months.
The following table outlines key terms related to the Company’s outstanding senior notes as of December 31, 2014:
					Unamortized (Discount) Premium
	Aggregate Principal Amount				2014				2013				Semi-annual interest		Issue Date	Maturity Date
													payments due
	(in thousands)
4.625% Notes	$	600,000			$	(42	)		$	(206	)		April 1 and October 1		20-Oct-09	April 1, 2015
7.00% Notes	500,000				—				—				April 15 and October 15		1-Oct-07	October 15, 2017
4.50% Notes	1,000,000				(369		)		(480		)		January 15 and July 15		7-Dec-10	January 15, 2018
3.40 % Notes (1)	1,000,000				5,509				(627		)		February 15 and August 15		19-Aug-13	February 15, 2019
7.25% Notes	300,000				(2,740		)		(3,252		)		May 15 and November 15		10-Jun-09	May 15, 2019
5.05% Notes	700,000				(504		)		(587		)		March 1 and September 1		16-Aug-10	September 1, 2020
3.450% Notes	650,000				(3,606		)		—				March 15 and September 15		7-Aug-14	September 15, 2021
5.90% Notes	500,000				(526		)		(586		)		May 1 and November 1		6-Oct-11	November 1, 2021
4.70% Notes	700,000				(1,013		)		(1,129		)		March 15 and September 15		12-Mar-12	March 15, 2022
3.50% Notes	1,000,000				(6,770		)		(7,480		)		January 31 and July 31		8-Jan-13	January 31, 2023
5.00% Notes (1)	1,000,000				10,834				(545		)		February 15 and August 15		19-Aug-13	February 15, 2024
__________
(1) The original issue date for the 3.40% Notes and the 5.00% Notes was August 19, 2013. The issue date for the reopened 3.40% Notes and the reopened 5.00% Notes was January 10, 2014.
The Company may redeem each of the series of senior notes at any time at a redemption price equal to 100% of the principal amount of such notes, plus a make-whole premium, together with accrued interest to the redemption date. Each of the applicable indentures, including any supplemental indentures (the “Indentures”) for the notes contain 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 shall not exceed 3.5x Adjusted EBITDA, as defined in the applicable Indenture for each of the notes. If the Company undergoes a change of control and ratings decline, each as defined in the Indentures, the Company may be required to repurchase one or more series of notes at a purchase price equal to 101% of the principal amount, plus accrued and unpaid interest (including additional interest, if any) up to, but not including, the date of repurchase. The 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 the Company’s subsidiaries.
Capital Lease and Other Obligations—The Company’s capital lease and other obligations approximated $95.4 million and $73.4 million as of December 31, 2014 and 2013, respectively. These obligations are secured by the related assets, bear interest at rates of 2.27% to 8.00%, and mature in periods ranging from less than one year to approximately seventy years.
Maturities—As of December 31, 2014, aggregate principal maturities of long-term debt, including capital leases, for the next five years and thereafter are expected to be (in thousands):
Year Ending December 31,
2015	$	897,624
2016	758,054
2017	706,488
2018	1,793,100
2019	3,163,859
Thereafter	7,254,208
Total cash obligations	14,573,333
Unamortized discounts and premiums, net	35,375
Balance as of December 31, 2014	$	14,608,708

Other_NonCurrent_Liabilities

Other Non-Current Liabilities	12 Months Ended
	Dec. 31, 2014
Other Liabilities, Noncurrent [Abstract]
Other Non-Current Liabilities	OTHER NON-CURRENT LIABILITIES
	Other non-current liabilities consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Unearned revenue	$	415,809	$	278,295
	Deferred rent liability	303,442		273,318
	Other miscellaneous liabilities	309,131		251,655
	Balance as of December 31,	$	1,028,382	$	803,268
	__________
	-1	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Asset_Retirement_Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation [Abstract]
Asset Retirement Obligations	ASSET RETIREMENT OBLIGATIONS
	The changes in the carrying amount of the Company’s asset retirement obligations are as follows (in thousands):
		2014			2013 (1)
	Beginning balance as of January 1,	$	549,548		$	435,624
	Additions	52,623			117,330
	Accretion expense	40,325			34,045
	Revisions in estimates (2)	(32,311		)	(36,492		)
	Settlements	(1,150		)	(959		)
	Balance as of December 31,	$	609,035		$	549,548
	__________
	-1	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
	-2	Revisions in estimates include the impact of approximately $(38.5) million and $(19.8) million of foreign currency translation for the years ended December 31, 2014 and 2013, respectively.
	As of December 31, 2014, the estimated undiscounted future cash outlay for asset retirement obligations is approximately $1.8 billion.

Derivative_Financial_Instrumen

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2014
Summary of Derivative Instruments [Abstract]
Derivative Financial Instruments	DERIVATIVE FINANCIAL INSTRUMENTS
	Certain of the Company’s foreign subsidiaries have entered into interest rate swap agreements, which have been designated as cash flow hedges, to manage exposure to variability in interest rates on debt.
	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 JIBAR over the term of the interest rate swap agreements. The notional value is reduced in accordance with the repayment schedule under the South African Facility.
	Colombia
	In connection with entering into the Colombian Credit Facility in October 2014, one of the Company’s Colombian subsidiaries entered into an interest rate swap agreement with an aggregate notional value of 100.0 billion COP (approximately $41.8 million) with certain of the lenders under the Colombian Credit Facility. The interest rate swap agreement matures on the earlier of termination of the underlying debt or April 24, 2021 and provides that the Company pay a fixed interest rate of 5.74% and receive variable interest at the three-month IBR over the term of the interest rate swap agreement. The notional value is reduced in accordance with the repayment schedule under the Colombian Credit Facility.
	In October 2014, the Company settled its previously existing interest rate swap related to the Colombian Long-Term Credit Facility and recognized a 3.0 billion COP (approximately $1.4 million) loss included in Loss on retirement of long-term obligations in the consolidated statements of operations.
	The notional amount and fair value of the interest rate swap agreements are as follows (in thousands):
		31-Dec-14					31-Dec-13
		Local		USD			Local		USD
	South Africa (ZAR)
	Notional	440,614		38,080			469,354		44,732
	Fair Value	1,016		88			939		90
	Colombia (COP)
	Notional	100,000,000		41,798			101,250,000		52,547
	Fair Value	(1,548,688	)	(647	)		(3,000,236	)	(1,557	)
	Costa Rica (USD) (1)
	Notional	—		—			N/A		42,000
	Fair Value	—		—			N/A		(628	)
	__________
	(1) One of the Company’s Costa Rican subsidiaries had three interest rate swap agreements, which were terminated upon repayment of the Costa Rica Loan in February 2014.
	As of December 31, 2014 and 2013, the South African interest rate swap agreements are in an asset position and are included in Notes receivable and other non-current assets on the consolidated balance sheets. The Colombian interest rate swap agreement is in a liability position and is included in Other non-current liabilities on the consolidated balance sheets.
	In addition to the interest rate swap agreements, the Company is amortizing the settlement cost of a treasury rate lock as additional interest expense over the term of the 7.00% senior unsecured notes due 2017.
	During the years ended December 31, 2014, 2013 and 2012, the interest rate swap agreements and treasury rate lock had the following impact on the Company’s consolidated financial statements (in thousands):
	Year Ended December 31,	Gain(Loss) Recognized in OCI - Effective Portion		Gain(Loss)		Location of Gain(Loss) Reclassified from AOCI into Income- Effective Portion (1)		Gain(Loss) Recognized		Location of Gain(Loss) Recognized in Income -
				Reclassified from				in Income - Ineffective Portion		Ineffective Portion
				AOCI into
				Income -
				Effective Portion
	2014	($2,082)		($3,606)		Interest expense/Loss on retirement of long-term obligations		N/A		N/A
	2013	$1,481		($2,809)		Interest expense		N/A		N/A
	2012	($6,220)		($1,340)		Interest expense		N/A		N/A
	__________
	(1) During the year ended December 31, 2014, amount includes $1.0 million reclassified from AOCI into Loss on retirement of long-term obligations in connection with the settlement of the interest rate swap related to the Colombian Long-Term Credit Facility.
	As of December 31, 2014, $0.7 million of the amount related to derivatives designated as cash flow hedges and recorded in AOCI is expected to be reclassified into earnings in the next twelve months.
	The Company also recognized a gain on the settlement of interest rate swap agreements entered into in connection with the 2007 Securitization.  The settlement was recognized as a reduction in interest expense over a five-year period for which the interest rate swaps were designated as hedges.  During the year ended December 31, 2012, the Company recorded $0.2 million as a reduction in interest expense. The remaining portion of the gain was fully amortized during the year ended December 31, 2012.
	For additional information on the Company’s interest rate swap agreements, see notes 12 and 13.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 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):
			December 31, 2014
			Fair Value Measurements Using								Assets/Liabilities
			Level 1		Level 2				Level 3		at Fair Value
	Assets:
	Short-term investments (1)				$	6,302					$	6,302
	Interest rate swap agreements				$	88					$	88
	Liabilities:
	Acquisition-related contingent consideration								$	28,524	$	28,524
	Interest rate swap agreements				$	647					$	647
			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 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 in connection with an acquisition with subsequent adjustments recognized in Other operating expenses in the 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 consolidated balance sheets and adjustments recorded in the consolidated statements of operations.
	As of December 31, 2014, the Company estimates that the value of all potential acquisition-related contingent consideration required payments to be between zero and $40.4 million. During the years ended December 31, 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	6,412				13,474
	Settlements	(3,889		)		(8,789		)
	Change in fair value	(225		)		5,743
	Foreign currency translation adjustment	(4,934		)		(2,249		)
	Other (1)	(730		)		—
	Balance as of December 31	$	28,524			$	31,890
	__________
	(1) In connection with the sale of operations in Panama, the buyer assumed the Company’s potential obligations related to additional purchase price
	consideration.
	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 year ended December 31, 2014, certain long-lived assets held and used with a carrying value of $8,900.0 million were written down to their net realizable value of $8,888.8 million as a result of an asset impairment charge of $11.2 million. During the year ended December 31, 2013, certain long-lived assets held and used with a carrying value of $8,554.5 million were written down to their net realizable value of $8,538.6 million, as a result of an asset impairment charge of $15.9 million. The asset impairment charges are recorded in Other operating expenses in the accompanying consolidated statements of operations. These adjustments were determined by comparing the estimated proceeds from the sale of assets or the estimated fair value utilizing projected future discounted cash flows to be provided from the long-lived assets to the asset’s carrying value.
	During the year ended December 31, 2014, NII, a U.S. corporation, filed for Chapter 11 bankruptcy protection on behalf of itself and certain of its subsidiaries. NII is the ultimate parent company of certain operating subsidiaries in Brazil, Chile and Mexico that collectively represent approximately 6% of the Company’s consolidated revenues for the year ended December 31, 2014. None of these subsidiaries were included in NII’s Chapter 11 filing. The Company’s assessment of the impact of the proceedings did not identify any indicators of impairment as of December 31, 2014.
	Sale of Assets—During the year ended December 31, 2014, the Company completed the sale of its operations in Panama and its third-party structural analysis business for an aggregate sale price of $17.9 million, plus a working capital adjustment. At the time of sale, the carrying amount of these assets primarily included $8.1 million of property and equipment, $7.8 million of intangible assets and $3.6 million of goodwill. The Company recorded a net charge of $2.2 million in Other operating expenses in the accompanying consolidated statements of operations.
	There were no other items measured at fair value on a nonrecurring basis during the year ended December 31, 2014.
	Fair Value of Financial Instruments—The Company’s financial instruments for which the carrying value reasonably approximates fair value at December 31, 2014 and 2013 include 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 is estimated using either indicative price quotes or a discounted cash flow analysis using rates for debt with similar terms and maturities. As of December 31, 2014, the carrying value and fair value of long-term obligations, including the current portion, are $14.6 billion and $15.0 billion, respectively, of which $9.7 billion is measured using Level 1 inputs and $5.3 billion is 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	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Accumulated Other Comprehensive Loss	ACCUMULATED OTHER COMPREHENSIVE LOSS
	The changes in Accumulated other comprehensive loss for the years ended December 31, 2014 and 2013, are as follows (in thousands):
		Unrealized Losses on Cash Flow Hedges			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 before reclassifications, net of tax	(1,966		)	—			(484,323		)	(486,289		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	2,490			798			—			3,288
	Net current-period other comprehensive income (loss)	524			798			(484,323		)	(483,001		)
	Balance as of December 31, 2014	$	(1,345	)	$	(2,231	)	$	(790,645	)	$	(794,221	)
		Unrealized Losses on Cash Flow Hedges			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	867			—			(131,160		)	(130,293		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	1,622			798			—			2,420
	Net current-period other comprehensive income (loss)	2,489			798			(131,160		)	(127,873		)
	Balance as of December 31, 2013	$	(1,869	)	$	(3,029	)	$	(306,322	)	$	(311,220	)
	During the year ended December 31, 2014, approximately $1.0 million was reclassified from Accumulated other comprehensive loss into Loss on retirement of long-term obligations in connection with the settlement of the interest rate swap related to the Colombian Long-Term Credit Facility. The remaining loss on cash flow hedges was reclassified into interest expense and the associated tax effect of $0.1 million and $0.2 million for the years ended December 31, 2014 and 2013, respectively, is included in Income tax provision.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income Taxes	INCOME TAXES
	The Company has filed, for prior taxable years through its taxable year ended December 31, 2011, consolidated U.S. federal tax returns, which included all of its then wholly owned domestic subsidiaries. For its taxable year commencing January 1, 2012, the Company filed, and intends to continue to file, as a REIT, and its domestic TRSs filed, and intend to continue to file, as C corporations. The Company also files tax returns in various states and countries. The Company’s state tax returns reflect different combinations of the Company’s subsidiaries and are dependent on the connection each subsidiary has with a particular state. The following information pertains to the Company’s income taxes on a consolidated basis.
	The income tax provision from continuing operations is comprised of the following for the years ended December 31, (in thousands):
		2014				2013				2012
	Current:
	Federal	$	(2,390	)		$	(30,322	)		$	(18,170	)
	State	(797		)		(13,731		)		(6,321		)
	Foreign	(57,934		)		(44,973		)		(53,513		)
	Deferred:
	Federal	(4,180		)		(16,318		)		(13,094		)
	State	(973		)		(5,139		)		(666		)
	Foreign	3,769				50,942				(15,540		)
	Income tax provision	$	(62,505	)		$	(59,541	)		$	(107,304	)
	The income tax provision for the years ended December 31, 2014 and 2013 include an expense of approximately $2.6 million and $21.5 million, respectively, resulting from the restructuring of certain of the Company’s domestic TRSs.
	The domestic and foreign components of income from continuing operations before income taxes and income on equity method investments are as follows for the years ended December 31, (in thousands):
		2014				2013				2012
	United States	$	857,457			$	766,772			$	787,960
	Foreign	8,247				(225,023		)		(86,666		)
	Total	$	865,704			$	541,749			$	701,294
	Reconciliation between the U.S. statutory rate and the effective rate from continuing operations is as follows for the years ended December 31:
		2014			2013			2012
	Statutory tax rate	35	%		35	%		35	%
	Tax adjustment related to REIT (1)	(35	)		(35	)		(35	)
	State taxes, net of federal benefit	1			3			1
	Foreign taxes	2			(5	)		4
	Foreign withholding taxes	3			6			4
	Domestic TRS restructuring	—			4			—
	Change in valuation allowance	—			—			8
	Other	1			3			(2	)
	Effective tax rate	7	%		11	%		15	%
	__________
	(1) Includes 24%, 28% and 18% from dividend paid deductions in 2014, 2013 and 2012, respectively.
	The components of the net deferred tax asset and related valuation allowance are as follows as of December 31, (in thousands):
		2014				2013 (1)
	Current assets:
	Allowances, accruals and other items not currently deductible	$	20,525			$	28,077
	Current deferred liabilities	(2,799		)		(4,547		)
	Subtotal	17,726				23,530
	Valuation allowance	(3,094		)		(3,638		)
	Net current deferred tax assets	$	14,632			$	19,892
	Non-current items:
	Assets:
	Net operating loss carryforwards	242,701				197,335
	Accrued asset retirement obligations	103,975				88,884
	Stock-based compensation	693				4,331
	Unearned revenue	18,947				46,788
	Unrealized loss on foreign currency	15,952				68,951
	Items not currently deductible and other	22,142				23,908
	Liabilities:
	Depreciation and amortization	(132,254		)		(82,068		)
	Deferred rent	(18,355		)		(17,814		)
	Other	(1,805		)		(5,302		)
	Subtotal	251,996				325,013
	Valuation allowance	(138,147		)		(132,368		)
	Net non-current deferred tax assets	$	113,849			$	192,645
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
	The Company’s deferred tax assets as of December 31, 2014 in the table above do not include $0.5 million of excess tax benefits from the exercise of employee stock options that are a component of NOLs as these benefits can only be recognized when the related tax deduction reduces income taxes payable.
	At December 31, 2014 and 2013, the Company has provided a valuation allowance of approximately $141.2 million and $136.0 million, respectively, which primarily relates to foreign items. During 2014, the Company increased amounts recorded as valuation allowances due to the uncertainty as to the timing of, and the Company’s ability to recover, net deferred tax assets in certain foreign operations in the foreseeable future. The amount of deferred tax assets considered realizable, however, could be adjusted if objective evidence in the form of cumulative losses is no longer present and additional weight may be given to subjective evidence such as the Company’s projections for growth.
	The recoverability of the Company’s net deferred tax asset has been assessed utilizing projections based on its current operations. Accordingly, the recoverability of the net deferred tax asset is not dependent on material asset sales or other non-routine transactions. Based on its current outlook of future taxable income during the carryforward period, management believes that the net deferred tax asset will be realized.
	The Company considers the earnings of certain non-U.S. subsidiaries to be indefinitely invested outside the United States on the basis of estimates that future domestic cash generation will be sufficient to meet future domestic cash needs. The Company has not recorded a deferred tax liability related to the U.S. federal and state income taxes and foreign withholding taxes on approximately $391.0 million of undistributed earnings of foreign subsidiaries indefinitely invested outside of the United States. Should the Company decide to repatriate the foreign earnings, it may have to adjust the income tax provision in the period it determined that the earnings will no longer be indefinitely invested outside of the United States.
	At December 31, 2014, the Company had net federal, state and foreign operating loss carryforwards available to reduce future taxable income, which includes losses of approximately $0.3 billion related to employee stock options. If not utilized, the Company’s net operating loss carryforwards expire as follows (in thousands):
	Years ended December 31,	Federal				State				Foreign
	2015 to 2019	$	—			$	82,656			$	11,896
	2020 to 2024	—				290,466				163,078
2025 to 2029	510,016				444,038				—
2030 to 2034	429,759				217,367				—
Indefinite carryforward	—				—				648,731
Total	$	939,775			$	1,034,527			$	823,705
Of the above $939.8 million of federal net operating loss carryforwards, $647.3 million is restricted to offset taxable income of the subsidiaries of the Company.
In addition, the Company has Mexican tax credits of $2.1 million, which if not utilized will expire in 2017.
As of December 31, 2014 and 2013, the total amount of unrecognized tax benefits that would impact the effective tax rate, if recognized, is $31.9 million and $31.1 million, respectively. 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, or if the applicable statute of limitations lapses. The impact of the amount of such changes to previously recorded uncertain tax positions could range from zero to $18.2 million. A reconciliation of the beginning and ending amount of unrecognized tax benefits are as follows for the years ended December 31, (in thousands):
	2014				2013				2012
Balance at January 1	$	32,545			$	34,337			$	38,886
Additions based on tax positions related to the current year	4,187				1,427				1,037
Additions for tax positions of prior years	3,780				—				—
Reductions for tax positions of prior years	—				(320		)		(221		)
Foreign currency	(3,216		)		(1,681		)		(439		)
Reduction as a result of the lapse of statute of limitations and effective settlements (1)	(5,349		)		(1,218		)		(4,926		)
Balance at December 31	$	31,947			$	32,545			$	34,337
(1) Includes $2.1 million of effective settlements for the year ended December 31, 2012.
During the years ended December 31, 2014, 2013 and 2012, the statute of limitations on certain unrecognized tax benefits lapsed and certain positions were effectively settled, which resulted in a decrease of $5.3 million, $1.2 million and $4.9 million, respectively, in the liability for uncertain tax benefits, all of which reduced the income tax provision.
The Company recorded penalties and tax-related interest expense (benefit) to the tax provision of ($3.4 million), $3.4 million and (2.9 million) for the years ended December 31, 2014, 2013 and 2012, respectively. As of December 31, 2014 and 2013, the total unrecognized tax benefits included in the consolidated balance sheets were $31.9 million and $32.5 million, respectively. As of December 31, 2014 and 2013, the total amount of accrued income tax-related interest and penalties included the consolidated balance sheets were $24.9 million and $30.9 million, respectively.
The Company has filed for prior taxable years, and for its taxable year ended December 31, 2014 will file, numerous consolidated and separate income tax returns, including U.S. federal and state tax returns and foreign tax returns. The Company is subject to examination in the U.S. and various state and foreign jurisdictions for certain tax years. As a result of the Company’s ability to carryforward federal, state and foreign NOLs, the applicable tax years generally remain open to examination several years after the applicable loss carryforwards have been used or expired. The Company regularly assesses the likelihood of additional assessments in each of the tax jurisdictions resulting from these examinations. The Company believes that adequate provisions have been made for income taxes for all periods through December 31, 2014.
In September 2013, the Internal Revenue Service released final Tangible Property Regulations (the “Final Regulations”). The Final Regulations provide guidance on applying Section 263(a) of the Code to amounts paid to acquire, produce or improve tangible property, as well as rules for materials and supplies (Code Section 162). These regulations contain certain changes from the temporary and proposed tangible property regulations that were issued on December 27, 2011. The Final Regulations are generally effective for taxable years beginning on or after January 1, 2014. In addition, taxpayers were permitted to early adopt the Final Regulations for taxable years beginning on or after January 1, 2012. The Final Regulations did not have a material effect on the Company’s results of operations or financial condition.

StockBased_Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2014
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION
	The Company recognized stock-based compensation expense of $80.2 million, $68.1 million and $52.0 million for the years ended December 31, 2014, 2013 and 2012, respectively. Stock-based compensation expense for the years ended December 31, 2013 included $1.1 million, related to the modification of the vesting and exercise terms for certain employees’ equity awards. The Company did not modify the vesting or exercise terms of equity awards during the years ended December 31, 2014 and 2012. The Company capitalized $1.6 million of stock-based compensation expense as property and equipment during each of the years ended December 31, 2014 and 2013.
	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 December 31, 2014, the Company has the ability to grant stock-based awards with respect to an aggregate of 14.3 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 that 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. Accordingly, for grants made on or after January 1, 2013, the Company recognizes compensation expense for all stock-based compensation over the shorter of (i) the four-year vesting period or (ii) the period from the date of grant to the date the employee becomes eligible for such retirement benefits, which may occur upon grant. Due to the accelerated recognition of stock-based compensation expense related to awards granted to retirement eligible employees, the Company recognized an incremental $14.8 million and $7.8 million of stock-based compensation expense during the years ended December 31, 2014 and 2013, respectively.
	Stock Options—The fair value of each option grant is estimated on the date of grant using the Black-Scholes option pricing model based on the assumptions noted in the table below. The risk-free interest rate is based on the U.S. Treasury yield approximating the estimated life in effect at the accounting measurement date. The expected life of option grants (estimated period of time outstanding) is estimated using the vesting term and historical exercise behavior of the Company’s employees. The expected volatility of the underlying stock price is based on historical volatility for a period equal to the expected life of the stock options. The expected annual dividend yield is the Company’s best estimate of expected future dividend yield.
	Key assumptions used to apply this pricing model are as follows:
		2014		2013		2012
	Range of risk-free interest rate	1.46% - 1.74%		0.75% - 1.42%		0.62% - 1.03%
	Weighted average risk-free interest rate	1.64%		0.91%		0.92%
	Expected life of option grants	4.5 years		4.4 years		4.4 years
	Range of expected volatility of the underlying stock price	21.94% - 23.35%		24.43% - 36.09%		36.53% - 37.86%
	Weighted average expected volatility of underlying stock price	23.08%		33.37%		37.84%
	Expected annual dividend yield	1.50%		1.50%		1.50%
	The weighted average grant date fair value per share during the years ended December 31, 2014, 2013 and 2012 was $14.86, $19.05 and $17.46, respectively. The intrinsic value of stock options exercised during the years ended December 31, 2014, 2013 and 2012 was $58.0 million, $42.1 million and $59.5 million, respectively. As of December 31, 2014, total unrecognized compensation expense related to unvested stock options is approximately $32.1 million and is expected to be recognized over a weighted average period of approximately two years. The amount of cash received from the exercise of stock options was approximately $56.6 million during the year ended December 31, 2014.
	The Company’s option activity for the year ended December 31, 2014 is as follows:
			Options			Weighted			Weighted		Aggregate
						Average			Average		Intrinsic Value
						Exercise Price			Remaining		(in millions)
									Life (Years)
	Outstanding as of January 1, 2014		6,106,171			$	52.81
	Granted		1,879,594			81.32
	Exercised		(1,267,320	)		44.63
	Forfeited		(176,522	)		74.8
	Expired		(33,488	)		33.46
	Outstanding as of December 31, 2014		6,508,435			$	62.14		6.77		$	238.9
	Exercisable as of December 31, 2014		2,992,252			$	46.77		4.84		$	155.8
	Vested or expected to vest as of December 31, 2014		6,506,185			$	62.13		6.77		$	238.9
	The following table sets forth information regarding options outstanding at December 31, 2014:
	Options Outstanding							Options Exercisable
	Outstanding		Range of Exercise		Weighted		Weighted Average	Options		Weighted
	Number of		Price Per Share		Average Exercise		Remaining Life	Exercisable		Average Exercise
	Options				Price Per Share		(Years)			Price Per Share
	1,553,717		$18.60 - $43.11		$36.04		3.54	1,553,717		$36.04
	971,207		44.92 - 58.60		49.25		5.2	744,434		48.63
	954,608		62.00 - 74.06		62.52		7.24	397,291		62.3
	1,232,856		76.90 - 79.45		76.95		8.2	256,378		76.92
	1,796,047		81.18 - 93.45		81.32		9.2	40,432		81.18
	6,508,435		$18.60 - $93.45		$62.14		6.77	2,992,252		$46.77
	Restricted Stock Units—The Company’s restricted stock unit activity during the year ended December 31, 2014 is as follows:
		Number of			Weighted Average Grant
		Units			Date Fair Value
	Outstanding as of January 1, 2014	1,840,137			$	64.75
	Granted	807,582			81.54
	Vested	(716,905	)		59.65
	Forfeited	(171,997	)		72.36
	Outstanding as of December 31, 2014	1,758,817			$	73.8
	Expected to vest, net of estimated forfeitures, as of December 31, 2014	1,685,937			$	73.59
	The total fair value of restricted stock units that vested during the year ended December 31, 2014 was $58.6 million.
	As of December 31, 2014, total unrecognized compensation expense related to unvested restricted stock units granted under the 2007 Plan is $76.3 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. 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. Employees may purchase shares having a value not exceeding 15% of their gross compensation during an offering period and may not purchase more than $25,000 worth of stock in a calendar year (based on market values at the beginning of each offering period). The offering periods run from June 1 through November 30 and from December 1 through May 31 of each year. During the 2014, 2013 and 2012 offering periods employee contributions were accumulated to purchase an estimated 81,000, 78,000 and 88,000 shares, respectively, at weighted average prices per share of $70.48, $64.74 and $51.59, respectively. During each six month offering period, employees accumulate payroll deductions to purchase the Company’s common stock. The fair value of the ESPP share purchase option is estimated on the offering period commencement date using a Black-Scholes pricing model with the expense recognized over the expected life, which is the six-month offering period. The weighted average fair value per share of ESPP share purchase options during the year ended December 31, 2014, 2013 and 2012 was $14.83, $13.42 and $13.64, respectively. At December 31, 2014, 3.4 million shares remain reserved for future issuance under the plan.
	Key assumptions used to apply the Black-Scholes pricing model for shares purchased through the ESPP for the years ended December 31, are as follows:
		2014		2013		2012
	Range of risk-free interest rate	0.06% - 0.11%		0.07% – 0.13%		0.05% – 0.12%
	Weighted average risk-free interest rate	0.09%		0.10%		0.08%
	Expected life of shares	6 months		6 months		6 months
	Range of expected volatility of underlying stock price over the option period	11.29% – 16.59%		12.21% – 13.57%		33.16% – 33.86%
	Weighted average expected volatility of underlying stock price	14.14%		12.88%		33.54%
	Expected annual dividend yield	1.50%		1.50%		1.50%

Equity

Equity	12 Months Ended
	Dec. 31, 2014
Stockholders' Equity Attributable to Parent [Abstract]
Equity	EQUITY
	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 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 (“2011 Buyback”). In September 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. For the year ended December 31, 2014, the Company received an aggregate of $62.3 million in proceeds upon exercises of stock options and from its ESPP.
	Distributions—The following tables characterize the tax treatment of distributions declared per share of common stock and preferred stock.
			For the year ended December 31,
			2014					2013				2012
			Per Share			%		Per Share		%		Per Share		%
	Common Stock
		Ordinary income	$	1.4		100	%	$	1.1	100	%	$	0.9	100	%
		Capital gain	—			—		—		—		—		—
		Return of capital	—			—		—		—		—		—
		Total	$	1.4		100	%	$	1.1	100	%	$	0.9	100	%
			For the year ended December 31,
			2014					2013 (2)				2012 (2)
			Per Share			%		Per Share		%		Per Share		%
	Preferred Stock
		Ordinary income	$	2.6688		100	%	$	—	—	%	$	—	—	%
		Capital gain	—			—		—		—		—		—
		Return of capital	—			—		—		—		—		—
		Total	$	2.6688	-1	100	%	$	—	—	%	$	—	—	%
	__________
	(1) In addition to the dividends disclosed above, on December 2, 2014, the Company declared a dividend of $1.3125 per share, payable on February 16, 2015 to
	preferred stockholders of record at the close of business on February 1, 2015.
	(2) The Company had no preferred stock outstanding during the years ended December 31, 2013 and 2012.
	The Company accrues distributions on unvested restricted stock units granted subsequent to January 1, 2012, which are payable upon vesting. As of December 31, 2014, the amount accrued for distributions payable related to unvested restricted stock units is $3.4 million. During the year ended December 31, 2014, the Company paid $0.7 million of distributions payable upon the vesting of restricted stock units.
	To maintain its qualification for taxation as a REIT, the Company expects to continue paying distributions, the amount, timing and frequency of which will be determined and be subject to adjustment by the Company’s Board of Directors.

Impairments_Net_Loss_on_Sale_o

Impairments, Net Loss on Sale of Long-Lived Assets	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment Impairment or Disposal [Abstract]
Impairments, Net Loss on Sale of Long-lived Assets	IMPAIRMENTS, NET LOSS ON SALES OF LONG-LIVED ASSETS
	During the years ended December 31, 2014, 2013 and 2012, the Company recorded impairment charges and net losses on sales or disposals of long-lived assets of $28.5 million, $32.5 million and $34.4 million, respectively. These charges are primarily related to assets included in the Company’s domestic rental and management segment and are included in Other operating expenses in the consolidated statements of operations.
	Included in these amounts are impairment charges of approximately $15.3 million, $15.9 million and $21.5 million for the years ended December 31, 2014, 2013 and 2012, respectively, to write down certain assets to net realizable value after an indicator of impairment was identified. Included in amounts recorded for the year ended December 31, 2012, was an impairment charge of approximately $10.8 million resulting from the impairment of one of the Company’s outdoor DAS networks upon the termination of a tenant lease.
	Also included in these amounts are net losses associated with the sale or disposal of certain non-core towers, other assets and other miscellaneous items of $13.2 million, $16.6 million and $12.9 million for the years ended December 31, 2014, 2013 and 2012, respectively.

Earnings_Per_Common_Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Common Share	EARNINGS PER COMMON SHARE
	The following table sets forth basic and diluted net income per common share computational data for the years ended December 31, 2014, 2013 and 2012 (in thousands, except per share data):
		2014				2013			2012
	Net income attributable to American Tower Corporation stockholders	$	824,910			$	551,333		$	637,283
	Dividends declared on preferred stock	(23,888		)		—			—
	Net income attributable to American Tower Corporation common stockholders	801,022				551,333			637,283
	Basic weighted average common shares outstanding	395,958				395,040			394,772
	Dilutive securities	4,128				4,106			4,515
	Diluted weighted average common shares outstanding	400,086				399,146			399,287
	Basic net income attributable to American Tower Corporation common stockholders per common share	$	2.02			$	1.4		$	1.61
	Diluted net income attributable to American Tower Corporation common stockholders per common share	$	2			$	1.38		$	1.6
	Shares Excluded From Dilutive Effect
	The following shares were not included in the computation of diluted earnings per share for the years ended December 31, 2014, 2013 and 2012 because the effect would be anti-dilutive (in thousands, on a weighted average basis):
		2014			2013			2012
	Restricted stock awards	5			—			2
	Stock options	1,290			1,161			981
	Preferred stock (1)	4,303			—			—
	__________
	(1) Issued on May 12, 2014.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 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 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.  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.
	Lease Obligations—The Company leases certain land, office and tower space under operating leases that expire over various terms. Many of the leases contain renewal options with specified increases in lease payments upon exercise of the renewal option. Escalation clauses present in operating leases, excluding those tied to CPI or other inflation-based indices, are recognized on a straight-line basis over the non-cancellable term of the leases.
	Future minimum rental payments under non-cancellable operating leases include payments for certain renewal periods at the Company’s option because failure to renew could result in a loss of the applicable communications sites and related revenues from tenant leases, thereby making it reasonably assured that the Company will renew the leases. Such payments at December 31, 2014 are as follows (in thousands):
	Year Ending December 31,
	2015	$	574,438
	2016	553,864
	2017	538,405
	2018	519,034
	2019	502,847
	Thereafter	4,214,600
	Total	$	6,903,188
	Aggregate rent expense (including the effect of straight-line rent expense) under operating leases for the years ended December 31, 2014, 2013 and 2012 approximated $655.0 million, $495.2 million and $419.0 million, respectively.
	Future minimum payments under capital leases in effect at December 31, 2014 are as follows (in thousands):
	Year Ending December 31,
	2015	$	15,589
	2016	14,049
	2017	12,905
	2018	12,456
	2019	10,760
	Thereafter	173,313
	Total minimum lease payments	239,072
	Less amounts representing interest	(143,690		)
	Present value of capital lease obligations	$	95,382
	Tenant Leases—The Company’s lease agreements with its tenants vary depending upon the region and the industry of the tenant, and typically have initial terms of at least ten years with multiple renewal terms at the option of the tenant.
	Future minimum rental receipts expected from tenants under non-cancellable operating lease agreements in effect at December 31, 2014 are as follows (in thousands):
	Year Ending December 31,
	2015	$	3,438,474
	2016	3,358,098
	2017	3,304,255
	2018	3,168,551
	2019	2,916,750
	Thereafter	10,495,554
	Total	$	26,681,682
	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 2,400 towers from AT&T with the lease commencing between December 2000 and August 2004. Substantially all of the towers are part of the Securitization. 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. During the year ended December 31, 2014, the Company purchased 27 of the subleased towers upon expiration of the applicable agreement for an aggregate purchase price of $8.8 million. The aggregate purchase option price for the remaining towers leased and subleased is approximately $644.9 million, and will accrete at a rate of 10% per annum through the applicable expiration of the lease or sublease of a site. As of December 31, 2014, the Company has purchased an aggregate of 31 of the subleased towers upon expiration of the applicable agreement. 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 CPI.
	ALLTEL Transaction—In December 2000, the Company entered into an agreement with ALLTEL, a predecessor entity to Verizon Wireless to acquire towers through a 15-year sublease agreement. Pursuant to the agreement, as amended, with Verizon Wireless, 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 $73.2 million as of December 31, 2014. At Verizon Wireless’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 $134.7 million in the aggregate based on the closing price at December 31, 2014.
	Guaranties and Indemnifications—The Company enters into agreements from time to time in the ordinary course of business pursuant to which it agrees to guarantee or indemnify third parties for certain claims. The Company has also entered into purchase and sale agreements relating to the sale or acquisition of assets containing customary indemnification provisions. The Company’s indemnification obligations under these agreements generally are limited solely to damages resulting from breaches of representations and warranties or covenants under the applicable agreements, but do not guaranty future performance. In addition, payments under such indemnification clauses are generally conditioned on the other party making a claim that is subject to whatever defenses the Company may have and are governed by dispute resolution procedures specified in the particular agreement. Further, the Company’s obligations under these agreements may be limited in duration and/or amount, and in some instances, the Company may have recourse against third parties for payments made by the Company. The Company has not historically made any material payments under these agreements and, as of December 31, 2014, is not aware of any agreements that could result in a material payment.
	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 INR (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.

Supplemental_Cash_Flow_Informa

Supplemental Cash Flow Information	12 Months Ended
	Dec. 31, 2014
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	SUPPLEMENTAL CASH FLOW INFORMATION
	Supplemental cash flow information and non-cash investing and financing activities for the years ended December 31, 2014, 2013 and 2012 are as follows (in thousands):
		2014		2013		2012
	Supplemental cash flow information:
	Cash paid for interest	$	548,089	$	397,366	$	366,458
	Cash paid for income taxes (net of refunds of $8,476, $19,701 and $20,847, respectively)	69,212		51,676		69,277
	Non-cash investing and financing activities:
	Increase (decrease) in accounts payable and accrued expenses for purchases of property and equipment and construction activities	1,121		9,147		(10,244		)
	Purchases of property and equipment under capital leases	36,486		27,416		19,219
	Fair value of debt assumed through acquisitions	463,135		1,576,186		—
	Settlement of accounts receivable related to acquisitions	31,849		—		—
	Conversion of third-party debt to equity	111,181		—		—

Business_Segments

Business Segments	12 Months Ended
	Dec. 31, 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 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 December 31, 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, Peru, South Africa and Uganda. In November 2014, the Company signed an agreement to acquire communications sites in Nigeria.
	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. 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, Gain (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 benefit (provision). 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 consolidated statements of operations and consolidated balance sheets.
	Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2014, 2013 and 2012 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; Gain (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 and income on equity method investments, as the amounts are not utilized in assessing each segment’s performance.
			Rental and Management								Total Rental and		Network		Other		Total
											Management		Development
	Year ended December 31, 2014		Domestic				International						Services
			(in thousands)
	Segment revenues		$	2,639,790			$	1,367,064			$	4,006,854	$	93,194			$	4,100,048
	Segment operating expenses (1)		515,742				539,038				1,054,780		37,648				1,092,428
	Interest income, TV Azteca, net		—				10,547				10,547		—				10,547
	Segment gross margin		2,124,048				838,573				2,962,621		55,546				3,018,167
	Segment selling, general, administrative and development expense (1)		124,944				133,978				258,922		12,469				271,391
	Segment operating profit		$	1,999,104			$	704,595			$	2,703,699	$	43,077			$	2,746,776
	Stock-based compensation expense														$	80,153	80,153
	Other selling, general, administrative and development expense														96,835		96,835
	Depreciation, amortization and accretion														1,003,802		1,003,802
	Other expense (principally interest expense and other expense)														700,282		700,282
	Income from continuing operations before income taxes and income on equity method investments																$	865,704
	Capital expenditures		$	576,153			$	374,105			$	950,258	$	—	$	24,146	$	974,404
	__________
	(1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of
	$1.8 million and $78.3 million, respectively.
			Rental and Management								Total Rental and		Network		Other		Total
											Management		Development
	Year ended December 31, 2013		Domestic				International						Services
			(in thousands)
	Segment revenues		$	2,189,365			$	1,097,725			$	3,287,090	$	74,317			$	3,361,407
	Segment operating expenses (1)		405,419				422,346				827,765		30,564				858,329
	Interest income, TV Azteca, net		—				22,235				22,235		—				22,235
	Segment gross margin		1,783,946				697,614				2,481,560		43,753				2,525,313
	Segment selling, general, administrative and development expense (1)		103,989				123,338				227,327		9,257				236,584
	Segment operating profit		$	1,679,957			$	574,276			$	2,254,233	$	34,496			$	2,288,729
	Stock-based compensation expense														$	68,138	68,138
	Other selling, general, administrative and development expense														112,367		112,367
	Depreciation, amortization and accretion														800,145		800,145
	Other expense (principally interest expense and other expense)														766,330		766,330
	Income from continuing operations before income taxes and income on equity method investments																$	541,749
	Capital expenditures		$	416,239			$	277,910			$	694,149	$	—	$	30,383	$	724,532
	__________
	(1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of
	$1.5 million and $66.6 million, respectively.
			Rental and Management								Total Rental and		Network		Other		Total
											Management		Development
	Year ended December 31, 2012		Domestic				International						Services
			(in thousands)
	Segment revenues		$	1,940,689			$	862,801			$	2,803,490	$	72,470			$	2,875,960
	Segment operating expenses (1)		357,555				328,333				685,888		34,830				720,718
	Interest income, TV Azteca, net		—				14,258				14,258		—				14,258
	Segment gross margin		1,583,134				548,726				2,131,860		37,640				2,169,500
	Segment selling, general, administrative and development expense (1)		85,663				95,579				181,242		6,744				187,986
	Segment operating profit		$	1,497,471			$	453,147			$	1,950,618	$	30,896			$	1,981,514
	Stock-based compensation expense														$	51,983	51,983
	Other selling, general, administrative and development expense														89,093		89,093
	Depreciation, amortization and accretion														644,276		644,276
	Other expense (principally interest expense and other expense)														494,868		494,868
	Income from continuing operations before income taxes and income on equity method investments																$	701,294
	Capital expenditures		$	268,997			$	279,004			$	548,001	$	—	$	20,047	$	568,048
	__________
	(1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of
$1.8 million and $50.2 million, respectively.
Additional information relating to the total assets of the Company’s operating segments for the years ended December 31, is as follows (in thousands):
	2014				2013 (1)				2012
Domestic rental and management	$	14,348,892			$	13,628,137			$	8,471,169
International rental and management (2)	6,776,013				6,428,438				5,190,987
Network development services	57,367				47,607				63,956
Other (3)	149,273				179,483				363,317
Total assets	$	21,331,545			$	20,283,665			$	14,089,429
__________
(1) Balances have been revised to reflect purchase accounting measurement period adjustments.
(2) Balances are translated at the applicable period end exchange rate and therefore may impact comparability between periods.
(3) Balances include corporate assets such as cash and cash equivalents, certain tangible and intangible assets and income tax accounts which have not been
allocated to specific segments.
Summarized geographic information related to the Company’s operating revenues for the years ended December 31, 2014, 2013 and 2012 and long-lived assets as of December 31, 2014 and 2013, is as follows (in thousands):
	2014				2013				2012
Operating Revenues:
United States	$	2,732,984			$	2,263,682			$	2,013,159
International (1):
Brazil	331,089				212,201				198,068
Chile	31,756				28,978				22,114
Colombia	89,421				70,901				48,424
Costa Rica	16,742				4,055				—
Germany	64,946				62,756				4,030
Ghana	95,486				92,114				81,818
India	219,566				191,355				181,863
Mexico	354,116				288,306				217,473
Panama (2)	1,243				424				—
Peru	8,078				5,824				5,310
South Africa	98,334				91,906				80,202
Uganda	56,287				48,905				23,499
Total international	1,367,064				1,097,725				862,801
Total operating revenues	$	4,100,048			$	3,361,407			$	2,875,960
__________
(1) Balances are translated at the applicable exchange rate and therefore may impact comparability between periods.
(2) In September 2014, the Company completed the sale of the operations in Panama.
	2014				2013 (1)
Long-Lived Assets (2):
United States	$	12,843,271			$	12,345,357
International (3):
Brazil	2,162,698				1,286,490
Chile	147,413				167,318
Colombia	320,355				390,197
Costa Rica	127,436				129,229
Germany	456,698				535,883
Ghana	235,523				304,603
India	616,266				610,744
Mexico	1,189,854				1,348,987
Panama (4)	—				17,177
Peru	61,490				58,220
South Africa	186,270				213,316
Uganda	185,956				195,128
Total international	5,689,959				5,257,292
Total long-lived assets	$	18,533,230			$	17,602,649
__________
(1) Balances have been revised to reflect purchase accounting measurement period adjustments.
(2) Includes Property and equipment, net, Goodwill and Other intangible assets, net.
(3) Balances are translated at the applicable period end exchange rate and therefore may impact comparability between periods.
(4) In September 2014, the Company completed the sale of the operations in Panama.
The following tenants within the domestic and international rental and management segments and network development services segment individually accounted for 10% or more of the Company’s consolidated operating revenues for the years ended December 31, 2014, 2013 and 2012 is as follows:
	2014			2013			2012
AT&T Mobility	20	%		18	%		18	%
Sprint Nextel	15	%		16	%		14	%
Verizon Wireless	11	%		11	%		11	%
T-Mobile	10	%		11	%		8	%

Related_Party_Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2014
Related Party Transaction, Due from (to) Related Party [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS
	During the years ended December 31, 2014, 2013, and 2012, the Company had no significant related party transactions.

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data	12 Months Ended
	Dec. 31, 2014
Selected Quarterly Financial Information [Abstract]
Selected Quarterly Financial Data (Unaudited)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)
	Selected quarterly financial data for the years ended December 31, 2014 and 2013 is as follows (in thousands, except per share data):
		Three Months Ended											Year Ended
		March 31,		June 30,			September 30,			December 31,			December 31,
	2014:00:00
	Operating revenues	$	984,089	$	1,031,457		$	1,038,188		$	1,046,314		$	4,100,048
	Cost of operations (1)	260,769		272,275			284,202			277,019			1,094,265
	Operating income	353,637		402,499			384,807			345,979			1,486,922
	Net income	193,313		221,659			206,630			181,597			803,199
	Net income attributable to American Tower Corporation stockholders	202,499		234,431			207,593			180,387			824,910
	Dividends declared on preferred stock	—		(4,375		)	(7,700		)	(11,813		)	(23,888		)
	Net income attributable to American Tower Corporation common stockholders	202,499		230,056			199,893			168,574			801,022
	Basic net income attributable to American Tower Corporation common stockholders	0.51		0.58			0.5			0.43			2.02
	Diluted net income attributable to American Tower Corporation common stockholders	0.51		0.58			0.5			0.42			2
		Three Months Ended											Year Ended
		March 31,		June 30,			September 30,			December 31,			December 31,
	2013:00:00
	Operating revenues	$	802,728	$	808,830		$	807,880		$	941,969		$	3,361,407
	Cost of operations (1)	201,766		205,709			200,829			251,569			859,873
	Operating income	299,686		312,812			308,879			292,928			1,214,305
	Net income	160,948		84,113			163,222			73,925			482,208
	Net income attributable to American Tower Corporation stockholders	171,407		99,821			180,123			99,982			551,333
	Dividends declared on preferred stock	—		—			—			—			—
	Net income attributable to American Tower Corporation common stockholders	171,407		99,821			180,123			99,982			551,333
	Basic net income attributable to American Tower Corporation common stockholders	0.43		0.25			0.46			0.25			1.4
	Diluted net income attributable to American Tower Corporation common stockholders	0.43		0.25			0.45			0.25			1.38
	__________
	(1) Represents Operating expenses, exclusive of Depreciation, amortization and accretion, Selling, general, administrative and development expense, and Other operating expense.

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS
	Redemption of 4.625% Senior Notes—On February 11, 2015, the Company redeemed all of the outstanding 4.625% senior notes due 2015 (the “4.625% Notes”). In accordance with the redemption provisions and the indenture for the 4.625% Notes, the 4.625% Notes were redeemed at a price equal to 100.5898% of the principal amount, plus accrued and unpaid interest up to, but excluding, February 11, 2015, for an aggregate purchase price of $613.6 million, including approximately $10.0 million of accrued and unpaid interest, which was funded with borrowings under the 2013 Credit Facility. Upon completion of this redemption, none of the 4.625% Notes remained outstanding.
	Proposed Verizon Transaction—On February 5, 2015, the Company announced that it has entered into a definitive agreement (the “Master Agreement”) pursuant to which American Tower expects to acquire rights to approximately 11,324 wireless communications towers and purchase approximately 165 additional towers from Verizon for $5.056 billion in cash at closing (the “Proposed Verizon Transaction”), subject to certain adjustments. Under the definitive agreement, American Tower will have the exclusive right to lease and operate the Verizon towers for a weighted average term of approximately 28 years. In addition, American Tower will have fixed price purchase options to acquire the towers based on their anticipated fair market values at the end of the lease terms. The Master Agreement contains various covenants and representations and warranties, which, among other things, includes the right of the Company and Verizon to terminate the Master Agreement if the Transaction does not close by August 4, 2015 (subject to extension to November 2, 2015 in certain circumstances). In addition, in certain circumstances, the Company may be required to pay a termination fee of approximately $354 million, in the event that the Verizon parties have irrevocably committed to consummate the Proposed Verizon Transaction, the conditions to the Company’s obligation to close the transaction have all been satisfied and the Company fails to consummate the Proposed Verizon Transaction.
	In addition, at closing, Verizon will contract to sublease space on the towers for a minimum of 10 years with monthly rent of $1,900 per site and fixed annual rent escalators of 2%. Verizon will have customary renewal options. Verizon will also have access to certain additional space on the towers for its future use, subject to certain restrictions. American Tower will have the right to sublease other available capacity on the towers to additional tenants.
	Amendments to Bank Facilities—On February 5, 2015 and February 20, 2015, the Company entered into amendment agreements with respect to the 2013 Term Loan, the 2013 Credit Facility and the 2014 Credit Facility. After giving effect to these amendments, the Company’s permitted ratio of Total Debt to Adjusted EBITDA (as defined in the loan agreements for each of the facilities) is (i) 6.00 to 1.00 for the fiscal quarters ended December 31, 2014 through the end of the fiscal quarter ending immediately prior to the closing of the Proposed Verizon Transaction, (ii) 7.25 to 1.00 for the first and second fiscal quarters ending on or after the closing of the Proposed Verizon Transaction, (iii) 7.00 to 1.00 for the two subsequent fiscal quarters and (iii) 6.00 to 1.00 thereafter. In addition, the maximum Incremental Term Loan Commitments (as defined in the agreement governing the 2013 Term Loan) was increased to $1.0 billion and the maximum Revolving Loan Commitments, after giving effect to any Incremental Commitments (each as defined in the loan agreements for each of the revolving credit facilities) was increased to $3.5 billion and $2.5 billion under the 2013 Credit Facility and the 2014 Credit Facility, respectively. Effective February 20, 2015, the Company received incremental commitments for an additional $500.0 million under each of the 2013 Term Loan and 2014 Credit Facility and $750.0 million under the 2013 Credit Facility. As a result, the Company has $2.0 billion outstanding under the 2013 Term Loan and may borrow up to $2.0 billion and $2.75 billion under the 2014 Credit Facility and the 2013 Credit Facility, respectively.
	Bridge Facility—In connection with the signing of a definitive agreement for the Proposed Verizon Transaction (the “Master Agreement”) the Company entered into a commitment letter (the “Commitment Letter”), dated February 5, 2015, with Goldman Sachs Bank USA and Goldman Sachs Lending Partners LLC (collectively, the “Commitment Parties”), pursuant to which the Commitment Parties have committed to provide up to $5.05 billion in bridge loans (the “Bridge Loan Commitment”) to ensure financing for the Proposed Verizon Transaction. Effective February 20, 2015, the Bridge Loan Commitment was reduced to $3.3 billion as a result of an aggregate of $1.75 billion of additional committed amounts under the Company’s existing bank facilities, as described above. The Bridge Loan Commitment will be further reduced on a dollar-for-dollar basis by, among other things, the net cash proceeds of any securities offering, debt incurrence and asset dispositions, subject to certain customary exceptions.
	The Bridge Loan Commitment will expire if the Company does not make any borrowings thereunder on the earliest to occur of (i) the consummation of the Proposed Verizon Transaction, (ii) the termination of the Master Agreement or the public announcement by the Company of the abandonment of the Proposed Verizon Transaction and (iii) August 5, 2015 (or November 3, 2015, if the Termination Date (as defined in the Master Agreement) is extended pursuant to the Master Agreement).
	The Commitment Letter contains, and the credit agreement in respect of the Bridge Loan Commitment, if any, will contain, certain customary conditions to funding, including, without limitation, (i) no material adverse effect with respect to Verizon’s land interests, towers, certain related improvements and tower related assets associated with each communications site having occurred since December 31, 2014, (ii) the execution and delivery of definitive financing agreements for the Bridge Loan Commitment and (iii) other customary closing conditions set forth in the Commitment Letter. The Company will pay certain customary commitment fees and, in the event the Company makes any borrowings, funding and other fees in connection with the Bridge Loan Commitment.

Schedule_III_Real_Estate_and_A

Schedule III - Real Estate and Accumulated Depreciation	12 Months Ended
	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Real Estate and Accumulated Depreciation Disclosure
	Description			Encumbrances					Initial cost		Cost		Gross amount			Accumulated			Date of	Date	Life on which
									to company		capitalized		carried at			depreciation at close of current period			construction	acquired	depreciation in
											subsequent to		close of current								latest income
											acquisition		period								statements is
																					computed
	75,164	sites (1)		$	3,510,481		-2		-3		-3		$	10,469,207	-4	$	(3,613,078	)	Various	Various	Up to 20 years
	-1	No single site exceeds 5% of the aggregate gross amounts at which the assets were carried at the close of the period set forth in the table above.
	-2	Certain assets secure debt of approximately $3.5 billion.
	-3	The Company has omitted this information, as it would be impracticable to compile such information on a site-by-site basis.
	-4	Does not include those sites under construction.
		2014 (1)				2013 (1)				2012
	Gross amount at beginning	$	9,921,276			$	8,290,313			$	7,192,641
	Additions during period:
	Acquisitions through foreclosure	—				—				—
	Other acquisitions (2)	397,837				1,415,171				739,144
	Discretionary capital projects (3)	437,720				314,126				217,935
	Discretionary ground lease purchases (4)	159,637				102,991				93,990
	Redevelopment capital expenditures (5)	96,782				89,960				67,309
	Capital improvements (6)	41,967				58,960				70,453
	Start-up capital expenditures (7)	21,173				15,757				—
	Other (8)	22,069				8,764				30,813
	Total additions	1,177,185				2,005,729				1,219,644
	Deductions during period:
	Cost of real estate sold or disposed	(60,147		)		(48,467		)		(15,288		)
	Other (9)	(569,107		)		(243,958		)		(80,450		)
	Total deductions:	(629,254		)		(292,425		)		(95,738		)
	Balance at end	$	10,469,207			$	10,003,617			$	8,316,547
	-1	Balance has been revised to reflect purchase accounting measurement period adjustments.
	-2	Includes acquisitions of sites.
	-3	Includes amounts incurred primarily for the construction of new sites.
	-4	Includes amounts incurred to purchase or otherwise secure the land under communications sites.
	-5	Includes amounts incurred to increase the capacity of existing sites, which results in new incremental tenant revenue.
	-6	Includes amounts incurred to maintain existing sites.
	-7	Includes amounts incurred for acquisitions and new market launches and costs that are contemplated in the business cases for these investments.
	-8	Primarily includes regional improvements and other additions.
	-9	Primarily includes foreign currency exchange rate fluctuations.
		2014				2013				2012
	Gross amount of accumulated depreciation at beginning	$	(3,297,033	)		$	(2,968,230	)		$	(2,646,927	)
	Additions during period:
	Depreciation	(457,135		)		(408,693		)		(344,778		)
	Other	(761		)		(264		)		(253		)
	Total additions	(457,896		)		(408,957		)		(345,031		)
	Deductions during period:
	Amount of accumulated depreciation for assets sold or disposed	20,953				17,462				10,920
	Other (1)	120,898				62,692				12,808
	Total deductions	141,851				80,154				23,728
	Balance at end	$	(3,613,078	)		$	(3,297,033	)		$	(2,968,230	)
	-1	Primarily includes foreign currency exchange rate fluctuations.

Business_and_Summary_of_Signif1

Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business	American Tower Corporation is, through its various subsidiaries (collectively, “ATC” or the “Company”), a global independent owner, operator and developer of communications real estate. The Company’s primary business is the leasing of 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.
	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 operates as a real estate investment trust for U.S. federal income tax purposes (“REIT”) and, therefore, is generally not subject to federal income taxes on its income and gains that it 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 taxable REIT subsidiaries (“TRSs”). 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 use of TRSs enables the Company to continue to engage in certain businesses while complying with REIT qualification requirements. 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 QRS as part of its REIT taxable income for the purpose of computing its REIT distribution requirements. During the year ended December 31, 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 a result, as of December 31, 2014, the Company’s QRSs include its domestic tower leasing business, most of its operations in Costa Rica, Germany and Mexico and a portion of its network development services segment and indoor DAS networks business.
Principles of Consolidation and Basis of Presentation	The accompanying 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 consolidated financial statements and accompanying notes. Actual results may differ from those estimates, and such differences could be material to the accompanying consolidated financial statements. The significant estimates in the accompanying 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.
Concentration of Credit Risk	The Company is subject to concentrations of credit risk related to its cash and cash equivalents, notes receivable, accounts receivable, deferred rent asset and derivative financial instruments. The Company mitigates its risk with respect to cash and cash equivalents and derivative financial instruments by maintaining its deposits and contracts at high quality financial institutions and monitoring the credit ratings of those institutions.
	The Company derives the largest portion of its revenues, corresponding accounts receivable and the related deferred rent asset from a relatively small number of tenants in the telecommunications industry, and approximately 56% of its current year revenues are derived from four tenants. In addition, the Company has concentrations of credit risk in certain geographic areas.
	The Company mitigates its concentrations of credit risk with respect to notes and trade receivables and the related deferred rent assets by actively monitoring the credit worthiness of its borrowers and tenants. In recognizing customer revenue, the Company must assess the collectibility of both the amounts billed and the portion recognized in advance of billing on a straight-line basis. This assessment takes tenant credit risk and business and industry conditions into consideration to ultimately determine the collectibility of the amounts billed. To the extent the amounts, based on management’s estimates, may not be collectible, recognition is deferred until such point as collectibility is determined to be reasonably assured. Any amounts that were previously recognized as revenue and subsequently determined to be uncollectible are charged to bad debt expense included in Selling, general, administrative and development expense in the accompanying consolidated statements of operations.
	Accounts receivable is reported net of allowances for doubtful accounts related to estimated losses resulting from a tenant’s inability to make required payments and allowances for amounts invoiced whose collectibility is not reasonably assured. These allowances are generally estimated based on payment patterns, days past due and collection history, and incorporate changes in economic conditions that may not be reflected in historical trends, such as tenants in bankruptcy, liquidation or reorganization. Receivables are written-off against the allowances when they are determined to be uncollectible. Such determination includes analysis and consideration of the particular conditions of the account.
Functional Currency	The functional currency of each of the Company’s foreign operating subsidiaries is the respective local currency, except for Costa Rica, 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 consolidated balance sheets and included as a component of comprehensive income.
	Transactional gains and losses on foreign currency transactions are reflected in Other expense in the 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 consolidated balance sheets and included as a component of comprehensive income.
Cash and Cash Equivalents	Cash and cash equivalents include cash on hand, demand deposits and short-term investments, including money market funds, with remaining maturities of three months or less when acquired, whose cost approximates fair value.
Restricted Cash	The Company classifies as restricted cash all cash pledged as collateral to secure obligations and all cash whose use is otherwise limited by contractual provisions, including cash on deposit in reserve accounts relating to the (i) Secured Tower Revenue Securities, Series 2013-1A and Series 2013-2A issued in the Company’s 2013 securitization transaction (the “Securities”), (ii) Secured Cellular Site Revenue Notes, Series 2010-1 Class C, Series 2010-2 Class C and Series 2010-2 Class F (collectively, the “Unison Notes”), assumed by the Company in connection with an acquisition and (iii) six series, consisting of eleven separate classes, of Secured Tower Revenue Notes, of which the Company repaid one series, consisting of two classes, in August 2014 (the remaining notes, the “GTP Notes”) assumed by the Company in connection with an acquisition.
Short-Term Investments	Short-term investments consists of highly-liquid investments with original maturities in excess of three months.
Property and Equipment	Property and equipment is recorded at cost or, in the case of acquired properties, at estimated fair value on the date acquired. Cost for self-constructed towers includes direct materials and labor, capitalized interest and certain indirect costs associated with construction of the tower, such as transportation costs, employee benefits and payroll taxes. The Company begins the capitalization of costs during the pre-construction period, which is the period during which costs are incurred to evaluate the site, and continues to capitalize costs until the tower is substantially completed and ready for occupancy by a tenant. Labor costs capitalized for the years ended December 31, 2014, 2013 and 2012 were $48.5 million, $44.1 million and $41.6 million, respectively. Interest costs capitalized for the years ended December 31, 2014, 2013 and 2012 were $2.8 million, $1.8 million and $1.9 million, respectively.
	Expenditures for repairs and maintenance are expensed as incurred. Augmentation and improvements that extend an asset’s useful life or enhance capacity are capitalized.
	Depreciation is recorded using the straight-line method over the assets’ estimated useful lives. Towers and related assets on leased land are depreciated over the shorter of the estimated useful life of the asset or the term of the corresponding ground lease, taking into consideration lease renewal options and residual value.
	Towers or assets acquired through capital leases are reflected in Property and equipment, net at the present value of future minimum lease payments or the fair value of the leased asset at the inception of the lease. Property and equipment, network location intangibles and assets held under capital leases are amortized over the shorter of the applicable lease term or the estimated useful life of the respective assets for periods generally not exceeding twenty years.
Goodwill and Other Intangible Assets	The Company reviews goodwill for impairment at least annually (as of December 31) or whenever events or circumstances indicate the carrying value of an asset may not be recoverable.
	Goodwill is recorded in the applicable segment and assessed for impairment at the reporting unit level. The Company utilizes the two-step impairment test when testing goodwill for impairment and employs a discounted cash flow analysis. The key assumptions utilized in the discounted cash flow analysis include current operating performance, terminal sales growth rate, management’s expectations of future operating results and cash requirements, the current weighted average cost of capital and an expected tax rate. Under the first step of this test, the Company compares the fair value of the reporting unit, as calculated under an income approach using future discounted cash flows, to the carrying amount of the applicable reporting unit. If the carrying amount exceeds the fair value, the Company conducts the second step of this test, in which the implied fair value of the applicable reporting unit’s goodwill is compared to the carrying amount of that goodwill. If the carrying amount of goodwill exceeds its implied fair value, an impairment loss would be recognized for the amount of the excess.
	During the years ended December 31, 2014, 2013 and 2012, no potential impairment was identified under the first step of the test, as the fair value of each of the reporting units was in excess of its carrying amount.
	Intangible assets that are separable from goodwill and are deemed to have a definite life are amortized over their useful lives, generally ranging from three to twenty years and are evaluated separately for impairment at least annually or whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable.
Deferred Rent Asset	The Company’s deferred rent asset is associated with non-cancellable tenant leases that contain fixed escalation clauses over the terms of the applicable lease in which revenue is recognized on a straight-line basis over the lease term.
Notes Receivable and Other Non-Current Assets	Notes receivable and other non-current assets primarily consists of prepaid ground lease assets, value added tax receivable, notes receivable from TV Azteca, long-term deposits, favorable leasehold interests and other non-current assets.
Derivatives Financial Instruments	Derivatives are recorded on the consolidated balance sheet at fair value. If a derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are recorded in AOCI, as well as a component of comprehensive income, and are recognized in the results of operations when the hedged item affects earnings. Changes in fair value of the ineffective portions of cash flow hedges are recognized 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 that the change occurs.
	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.
	The Company assesses, both at the inception of the hedge and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in cash flows of hedged items. The Company does not hold derivatives for trading purposes.
	The Company may also enter into foreign currency financial instruments in anticipation of future transactions in order to minimize the risk of currency fluctuations. These transactions do not typically qualify for hedge accounting, and as a result, the associated gains and losses are recognized in Other income (expense) in the consolidated statements of operations.
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.
Discount and Premium on Notes	The Company amortizes the discounts and premiums on its notes using the effective interest method over the term of the obligation. Such amortization is reflected in Interest expense and Interest income, TV Azteca, net in the accompanying consolidated statements of operations.
Asset Retirement Obligations	When required, the Company recognizes the fair value of obligations to remove its tower assets and remediate the leased land upon which certain of its tower assets are located. Generally, the associated retirement costs are capitalized as part of the carrying amount of the related tower assets and depreciated over their estimated useful lives and the liability is accreted through the obligation’s estimated settlement date. Fair value estimates of asset retirement obligations generally involve discounting of estimated future cash flows. Periodic accretion of such liabilities due to the passage of time is included in Depreciation, amortization and accretion in the consolidated statements of operations. Adjustments are also made to the asset retirement obligation liability to reflect changes in the estimates of timing and amount of expected cash flows, with an offsetting adjustment made to the related tangible long-lived asset. The significant assumptions used in estimating the Company’s aggregate asset retirement obligation are: timing of tower removals; cost of tower removals; timing and number of land lease renewals; expected inflation rates; and credit-adjusted, risk-free interest rates that approximate the Company’s incremental borrowing rate.
Income Taxes	As a REIT, the Company is generally not subject to federal income taxes on income and gains distributed to the Company’s stockholders. However, the Company remains obligated to pay income taxes on earnings from domestic TRSs. In addition, the Company’s international assets and operations continue to be subject to taxation in the foreign jurisdictions where those assets are held or where those operations are conducted, including those designated as QRSs for federal income tax purposes. Accordingly, the consolidated financial statements reflect provisions for federal, state, local and foreign income taxes. The Company recognizes deferred tax assets and liabilities for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis, as well as operating loss and tax credit carryforwards. The Company measures deferred tax assets and liabilities using enacted tax rates expected to apply to taxable income in the years in which those temporary differences and carryforwards are expected to be recovered or settled. The effect on deferred tax assets and liabilities as a result of a change in tax rates is recognized in income in the period that includes the enactment date.
	The Company periodically reviews its deferred tax assets, and records a valuation allowance 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. Valuation allowances would be reversed as a reduction to the provision for income taxes if related deferred tax assets are deemed realizable based on changes in facts and circumstances relevant to the assets’ recoverability.
	The Company classifies uncertain tax positions as non-current income tax liabilities unless expected to be paid within one year. The Company reports penalties and tax-related interest expense as a component of the income tax provision and interest income from tax refunds as a component of Other income (expense) in the consolidated statements of operations.
Other Comprehensive Income (Loss)	Other comprehensive income (loss) refers to items excluded from net income that are recorded as an adjustment to equity, net of tax. The Company’s other comprehensive income (loss) is primarily comprised of changes in fair value of effective derivative cash flow hedges, foreign currency translation adjustments and reclassification of unrealized losses on effective derivative cash flow hedges.
Treasury Stock	The Company records repurchases of its common stock using the cost method, whereby the purchase price, including legal costs and commissions, is recorded in a contra equity account, Treasury stock. The equity accounts from which the shares were originally issued are not adjusted for any treasury stock purchases unless and until such time as the shares are formally retired or reissued. As part of the Company’s conversion to a REIT, all treasury stock outstanding at the time was retired.
Distributions	As a REIT, the Company must annually distribute to its stockholders an amount equal to at least 90% of its REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain). Generally, the Company has distributed, and expects to continue to distribute all or substantially all of its REIT taxable income after taking into consideration its utilization of net operating loss carryforwards (“NOLs”). During the years ended December 31, 2014, 2013 and 2012, the Company declared regular cash distributions to its common stockholders of an aggregate of $554.6 million, or $1.40 per share, $434.5 million, or $1.10 per share, and $355.6 million, or $0.90 per share, respectively.
	During the year ended December 31, 2014, the Company declared an aggregate of $23.9 million, or $3.98 per share in cash distributions to its preferred stockholders.
	The amount, timing and frequency of future distributions will be at the sole discretion of the Board of Directors and will be declared based upon various factors, a number of which may be beyond the Company’s control, including the financial condition and operating cash flows, the amount required to maintain its qualification for taxation as a REIT and reduce any income and excise taxes that the Company otherwise would be required to pay, limitations on distributions in the Company’s existing and future debt and preferred equity instruments, the Company’s ability to utilize NOLs to offset the Company’s distribution requirements, limitations on its ability to fund distributions using cash generated through its TRSs and other factors that the Board of Directors may deem relevant.
Acquisitions	For acquisitions that meet the definition of a business combination, the Company applies the acquisition method of accounting where assets acquired and liabilities assumed are recorded at fair value at the date of each acquisition, and the results of operations are included with those of the Company from the dates of the respective acquisitions. Any excess of the purchase price paid by the Company over the amounts recognized for assets acquired and liabilities assumed is recorded as goodwill. The Company continues to evaluate acquisitions for a period not to exceed one year after the applicable acquisition date of each transaction to determine whether any additional adjustments are needed to the allocation of the purchase price paid for the assets acquired and liabilities assumed. The fair value of the assets acquired and liabilities assumed is typically determined by using either estimates of replacement costs or discounted cash flow valuation methods. When determining the fair value of tangible assets acquired, the Company must estimate the cost to replace the asset with a new asset taking into consideration such factors as age, condition and the economic useful life of the asset. When determining the fair value of intangible assets acquired, the Company must estimate the applicable discount rate and the timing and amount of future customer cash flows, including rate and terms of renewal and attrition.
Revenue Recognition	The Company’s revenue from leasing arrangements, including fixed escalation clauses present in non-cancellable lease agreements, is reported on a straight-line basis over the term of the respective leases when collectibility is reasonably assured. Escalation clauses tied to the Consumer Price Index (“CPI”) or other inflation-based indices, and other incentives present in lease agreements with the Company’s tenants are excluded from the straight-line calculation. Total rental and management straight-line revenues for the years ended December 31, 2014, 2013 and 2012 approximated $123.7 million, $147.7 million and $165.8 million, respectively. Amounts billed upfront in connection with the execution of lease agreements are initially deferred and reflected in Unearned revenue in the accompanying consolidated balance sheets and recognized as revenue over the terms of the applicable leases. Amounts billed or received for services prior to being earned are deferred and reflected in Unearned revenue in the accompanying consolidated balance sheets until the criteria for recognition have been met.
	Network development services revenues are derived under contracts or arrangements with customers that provide for billings either on a fixed price basis or a variable price basis, which includes factors such as time and expenses. Revenues are recognized as services are performed, and include estimates for percentage completed. Amounts billed or received for services prior to being earned are deferred and reflected in Unearned revenue in the accompanying consolidated balance sheets until the criteria for recognition have been met.
Rent Expense	Many of the leases underlying the Company’s tower sites have fixed rent escalations, which provide for periodic increases in the amount of ground rent payable by the Company over time. In addition, certain of the Company’s tenant leases require the Company to exercise available renewal options pursuant to the underlying ground lease if the tenant exercises its renewal option. The Company calculates straight-line ground rent expense for these leases based on the fixed non-cancellable term of the underlying ground lease plus all periods, if any, for which failure to renew the lease imposes an economic penalty to the Company such that renewal appears to be reasonably assured.
	Total rental and management straight-line ground rent expense for the years ended December 31, 2014, 2013 and 2012 approximated $38.4 million, $29.7 million and $33.7 million, respectively. The Company’s liability for straight-line ground rent expense is recorded in Other non-current liabilities. The Company records prepaid ground rent in Prepaid and other current assets and Notes receivable and other non-current assets in the accompanying consolidated balance sheets according to the anticipated period of benefit.
Selling, General, Administrative and Development Expense	Selling, general and administrative expense consists of overhead expenses related to the Company’s rental and management and services operations and corporate overhead costs not specifically allocable to any of the Company’s individual business operations. Development expense consists of costs related to the Company’s acquisition efforts, costs associated with new business initiatives and project cancellation costs.
Stock-based Compensation	Stock-based compensation expense is measured at the accounting measurement date based on the fair value of the award and is recognized as an expense over the service period, which generally represents the vesting period. 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 that 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. Accordingly, for grants made on or after January 1, 2013, the Company recognizes compensation expense for all stock-based compensation over the shorter of (i) the four-year vesting period or (ii) the period from the date of grant to the date the employee becomes eligible for such retirement benefits, which may occur upon grant. The expense recognized over the service period includes an estimate of awards that will not fully vest and be forfeited. The fair value of stock options is determined using the Black-Scholes option-pricing model and the fair value of restricted stock units is based on the fair value of the Company’s common stock on the date of grant. The Company recognizes stock-based compensation expense in either Selling, general, administrative and development expense, costs of operations or as part of the costs associated with the construction of the tower assets.
Litigation Costs	The Company periodically becomes involved in various claims and lawsuits that are incidental to its business. The Company regularly monitors the status of pending legal actions to evaluate both the magnitude and likelihood of any potential loss. The Company accrues for these potential losses when it is probable that a liability has been incurred and the amount of loss, or possible range of loss, can be reasonably estimated. Should the ultimate losses on contingencies or litigation vary from estimates, adjustments to those liabilities may be required. The Company also incurs legal costs in connection with these matters and records estimates of these expenses, which are reflected in Selling, general, administrative and development expense in the accompanying consolidated statements of operations.
Other Operating Expenses	Other operating expenses includes the costs incurred by the Company in conjunction with acquisitions and mergers (including changes in estimated fair value of contingent consideration), impairments on long-lived assets and gains and losses recognized upon the disposal of long-lived assets and other discrete items of a non-recurring nature.
	The Company reviews long-lived assets, including intangible assets subject to amortization, for impairment whenever events, changes in circumstances or other evidence indicate that the carrying amount of the Company’s assets may not be recoverable.
	The Company reviews its tower portfolio and network location intangible assets for indications of impairment on an individual tower basis. Impairments primarily result from a tower not having current tenant leases or from having expenses in excess of revenues. The Company monitors its customer-related intangible assets on a customer by customer basis for indicators of impairment, such as high levels of turnover or attrition, non-renewal of a significant number of contracts, or the cancellation or termination of a relationship. The Company assesses recoverability by determining whether the carrying amount of the related assets will be recovered, either through projected undiscounted future cash flows or anticipated proceeds from sales of the assets. If the Company determines that the carrying amount of an asset may not be recoverable, the Company will measure any impairment loss based on the projected future discounted cash flows to be provided from the asset or available market information relative to the asset’s fair value, as compared to the asset’s carrying amount. The Company records any related impairment charge in the period in which the Company identifies such impairment.
Loss on Retirement of Long-Term Obligations	Loss on retirement of long-term obligations primarily includes cash paid to retire debt in excess of its carrying value, non-cash charges related to the write-off of deferred financing fees, losses associated with the settlement of interest rate swaps and the write-off of any discounts or premiums. In 2014, Loss on retirement of long-term obligations includes amounts associated with the acquisition of BR Towers’ preferred equity.
Earnings Per Common Share-Basic and Diluted	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. Dilutive common share equivalents also include the dilutive impact of the ALLTEL transaction. 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.
Retirement Plan	The Company has a 401(k) plan covering substantially all employees who meet certain age and employment requirements. For the years ended December 31, 2014 and 2013, the Company matched 75% of the first 6% of a participant’s contributions. The Company’s matching contribution for the year ended December 31, 2012 was 50% of the first 6% of a participant’s contributions.
Accounting Standards Update	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 is 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 chose to early adopt this guidance during the year ended December 31, 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 and will become effective on January 1, 2017. The standard permits the use of either the retrospective or cumulative effect transition method, and leases are not included in the scope of this standard. The Company is evaluating the impact this standard may have on its financial statements.

Business_and_Summary_of_Signif2

Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Changes in allowances	Changes in the allowances were as follows for the years ended December 31, (in thousands):
		2014			2013			2012
	Balance as of January 1	$	19,895		$	20,406		$	24,412
	Current year increases	8,243			7,025			8,028
	Write-offs, net of recoveries and other	(10,832		)	(7,536		)	(12,034		)
	Balance as of December 31	$	17,306		$	19,895		$	20,406

Recovered_Sheet1

Prepaid And Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid and other current assets	Prepaid and other current assets consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Prepaid operating ground leases	$	88,508	$	96,881
	Prepaid income tax	34,512		52,612
	Unbilled receivables	25,352		25,412
	Prepaid assets	23,848		34,243
	Value added tax and other consumption tax receivables	23,228		77,016
	Other miscellaneous current assets	59,174		61,253
	Balance as of December 31,	$	254,622	$	347,417
	__________
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Property and equipment	Property and equipment (including assets held under capital leases) consists of the following as of December 31, (in thousands):
		Estimated	2014			2013 (2)
		Useful  Lives (years) (1)
	Towers	Up to 20	$	8,300,387		$	7,933,917
	Equipment	15-Feb	995,667			762,738
	Buildings and improvements	Mar-32	618,889			607,540
	Land and improvements (3)	Up to 20	1,566,096			1,369,969
	Construction-in-progress		214,760			170,292
	Total		11,695,799			10,844,456
	Less accumulated depreciation and amortization		(4,068,982		)	(3,666,728		)
	Property and equipment, net		$	7,626,817		$	7,177,728
	__________
	(1) Assets on leased land are depreciated over the shorter of the estimated useful life of the asset or the term of the corresponding ground lease taking into
	consideration lease renewal options and residual value.
	(2) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
	(3) Estimated useful lives apply to land improvements only.

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 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, 2013		$	2,320,571			$	520,072			$	2,000			$	2,842,643
	Additions		973,328				91,249				—				1,064,577
	Effect of foreign currency translation		—				(52,418		)		—				(52,418		)
	Balance as of December 31, 2013 (1)		$	3,293,899			$	558,903			$	2,000			$	3,854,802
	Additions		48,247				168,966				—				217,213
	Effect of foreign currency translation		—				(51,280		)		—				(51,280		)
	Other (2)		—				(3,641		)		(12		)		(3,653		)
	Balance as of December 31, 2014		$	3,342,146			$	672,948			$	1,988			$	4,017,082
	__________
	(1) Balances have been revised to reflect purchase accounting measurement period adjustments.
	(2) Other represents the goodwill associated with the Company’s operations in Panama and the Company’s third-party structural analysis business. Both businesses were sold during the year ended December 31, 2014 (see note 12).
Finite Intangible Assets	The Company’s other intangible assets subject to amortization consist of the following:
					As of December 31, 2014												As of December 31, 2013 (1)
		Estimated Useful			Gross				Accumulated				Net Book				Gross		Accumulated			Net Book
		Lives			Carrying				Amortization				Value				Carrying		Amortization			Value
					Value												Value
		(years)			(in thousands)
	Acquired network location intangibles(2)	Up to 20			$	2,513,763			$	(901,903	)		$	1,611,860			$	2,418,153	$	(791,359	)	$	1,626,794
	Acquired customer-related intangibles	15-20			6,579,094				(1,429,572		)		5,149,522				6,017,849		(1,170,239		)	4,847,610
	Acquired licenses and other intangibles	20-Mar			43,012				(3,514		)		39,498				6,583		(2,297		)	4,286
	Economic Rights, TV Azteca	70			25,522				(12,960		)		12,562				28,783		(14,229		)	14,554
	Total				$	9,161,391			$	(2,347,949	)		$	6,813,442			$	8,471,368	$	(1,978,124	)	$	6,493,244
	Deferred financing costs, net (3)	N/A											75,889									76,875
	Other intangible assets, net												$	6,889,331								$	6,570,119
	__________
	(1) December 31, 2013 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 next five subsequent years (in millions):
	Year Ending December 31,
	2015	$	430.8
	2016	424.4
	2017	422.7
	2018	421.8
	2019	419.9

Notes_Receivable_and_Other_Non1

Notes Receivable and Other Non-current Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Notes Receivable And Other Long Term Assets [Abstract]
Notes receivable and other non-current assets	Notes receivable and other non-current assets consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Long-term prepaid ground rent	$	310,232	$	217,983
	Notes receivable	87,515		89,381
	Other miscellaneous assets	168,707		201,809
	Balance as of December 31,	$	566,454	$	509,173
	__________
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2014
Business Combination, Description [Abstract]
Schedule of recognized identified assets acquired and liabilities assumed	The following table summarizes the preliminary allocation, unless otherwise noted, of the 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.
	The following table summarizes the preliminary allocation, unless otherwise noted, of the purchase price 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 consolidated balance sheets as of December 31, 2014.
			BR Towers			Richland				International (1)				Other U.S.
	Current assets		$	31,832		$	8,583			$	7,072			$	797
	Non-current assets		9,135			—				1,521				—
	Property and equipment		141,422			185,777				32,225				38,413
	Intangible assets (2):
	Customer-related intangible assets		495,279			169,452				20,217				89,990
	Network location intangible assets		136,233			1,700				10,729				39,470
	Other intangible assets		37,664			—				—				—
	Current liabilities		(23,930		)	(3,635		)		(863		)		(1,997		)
	Other non-current liabilities		(101,508		)	(2,922		)		(6,263		)		(1,675		)
	Net assets acquired		726,127			358,955				64,638				164,998
	Goodwill (3)		164,955			32,423				4,011				15,824
	Fair value of net assets acquired		891,082			391,378				68,649				180,822
	Debt assumed (4)		(261,136		)	(201,999		)		—				—
	Preferred stock outstanding		(61,056		)	—				—				—
	Purchase Price		$	568,890		$	189,379			$	68,649			$	180,822
	__________
	-1	The allocation of the purchase price was finalized during the year ended December 31, 2014.
	-2	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years. Other intangible assets are amortized on a straight-line basis over the life of the lease, which is a period of 11 years.
	-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 except for goodwill associated with BR Towers where goodwill is expected to be partially deductible.
	-4	BR Towers debt assumed approximated fair value at the date of acquisition and includes $11.5 million of current indebtedness. Richland debt assumed includes $196.5 million of Richland’s 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.
	The following table summarizes the allocation of the 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).
			Final 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		10,102				10,021
	Prepaid and other current assets		40,865				22,875
	Property and equipment		910,713				996,901
	Intangible assets (3):
	Customer-related intangible assets		2,456,582				2,629,188
	Network location intangible assets		528,900				467,300
	Notes receivable and other non-current assets		68,388				4,220
	Accounts payable		(9,969		)		(9,249		)
	Accrued expenses		(42,867		)		(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		(57,965		)		(43,089		)
	Other non-current liabilities		(17,837		)		(37,326		)
	Fair value of net assets acquired		$	2,338,418			$	2,455,495
	Goodwill (5)		992,044				874,967
	__________
	(1) Balances are reflected as updated in the accompanying consolidated balance sheets as of December 31, 2013.
	(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.
The following table summarizes the updated allocation of the 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 consolidated balance sheets herein.
		Axtel Mexico (1)				NII Mexico (2) (3)				NII Brazil (2)				Z-Sites (2)			Other International (2)			Other U.S. (2)
Current assets		$	—			$	59,938			$	—			$	—		$	4,863		$	1,220
Non-current assets		2,626				10,738				9,534				6,718			1,991			44
Property and equipment		86,100				143,680				109,426				26,881			44,844			23,537
Intangible assets (4):
Customer-related intangible assets		119,392				132,897				142,125				62,286			20,590			29,325
Network location intangible assets		43,031				66,069				82,111				17,350			20,727			7,935
Current liabilities		—				—				—				—			—			(454		)
Other non-current liabilities		(9,377		)		(10,478		)		(20,100		)		(2,331		)	(8,168		)	(848		)
Fair value of net assets acquired		$	241,772			$	402,844			$	323,096			$	110,904		$	84,847		$	60,759
Goodwill (5)		6,751				25,056				18,312				13,040			4,970			4,403
__________
-1	The allocation of the purchase price was finalized during the year ended December 31, 2013.
-2	The allocation of the purchase price was finalized during the year ended December 31, 2014.
-3	Current assets includes approximately $59.0 million of value added tax.
-4	Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years.
-5	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 year ended December 31, 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.
Pro forma information	The following table presents the unaudited pro forma financial results as if the 2014 acquisitions had occurred on January 1, 2013 and the 2013 acquisitions had occurred on January 1, 2012 (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.
			Year Ended December 31,
			2014				2013
	Pro forma revenues		$	4,193,067			$	3,848,549
	Pro forma net income attributable to American Tower Corporation common stockholders		$	770,871			$	394,253
	Pro forma net income per common share amounts:
	Basic net income attributable to American Tower Corporation common stockholders		$	1.95			$	1
	Diluted net income attributable to American Tower Corporation common stockholders		$	1.93			$	0.99

Accrued_Expenses_Tables

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2014
Accrued Liabilities, Current [Abstract]
Schedule of accrued expenses	Accrued expenses consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Accrued property and real estate taxes	$	61,206	$	54,529
	Payroll and related withholdings	57,110		50,843
	Accrued construction costs	46,024		52,446
	Accrued rent	34,074		28,456
	Other accrued expenses	219,340		234,914
	Balance as of December 31,	$	417,754	$	421,188
	__________
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

LongTerm_Obligations_Tables

Long-Term Obligations (Tables)	12 Months Ended
	Dec. 31, 2014
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term financing arrangements	Outstanding amounts under the Company’s long-term obligations consist of the following as of December 31, (in thousands):
				2014				2013				Contractual Interest Rate (1)			Maturity Date (1)
		American Tower subsidiary debt:
			Secured Tower Revenue Securities, Series 2013-1A	$	500,000			$	500,000			1.551	%		March 15, 2018 (2)
			Secured Tower Revenue Securities, Series 2013-2A	1,300,000				1,300,000				3.07	%		March 15, 2023 (2)
			GTP Notes (3)	1,263,983				1,537,881				2.364% - 7.628%			Various
			BR Towers Debentures (4)	118,688				—				7.4	%		October 15, 2023
			BR Towers Credit Facility (4)	16,389				—				3.500% - 10.800%			Various
			Unison Notes (5)	203,683				205,436				5.349% - 9.522%			Various
			Mexican Loan (6)(7)	263,426				377,470				4.821	%		May 1, 2015
			South African Facility (6)(8)	75,133				88,334				9.875	%		March 31, 2020
			Colombian Credit Facility (6)(9)	83,596				—				8.36	%		April 24, 2021
			Colombian Long-Term Credit Facility	—				70,063				N/A			N/A
			Colombian Bridge Loans	—				56,058				N/A			N/A
			Colombian Loan	—				35,697				N/A			N/A
			Costa Rica Loan	—				32,600				N/A			N/A
			Shareholder loans (10)	137,655				225,253				Various			Various
		Total American Tower subsidiary debt		3,962,553				4,428,792
		American Tower Corporation debt:
			2013 Credit Facility (6)	—				1,853,000				1.41	%		June 28, 2018
			2013 Term Loan (6)	1,500,000				1,500,000				1.41	%		January 3, 2019
			2014 Credit Facility (6)(11)	1,100,000				88,000				1.41	%		January 31, 2020
			4.625% Notes (12)	599,958				599,794				4.625	%		April 1, 2015
			7.00% Notes	500,000				500,000				7	%		October 15, 2017
			4.50% Notes	999,631				999,520				4.5	%		January 15, 2018
			3.40% Notes	1,005,509				749,373				3.4	%		February 15, 2019
			7.25% Notes	297,260				296,748				7.25	%		May 15, 2019
			5.05% Notes	699,496				699,413				5.05	%		September 1, 2020
			3.450% Notes	646,394				—				3.45	%		September 15, 2021
			5.90% Notes	499,474				499,414				5.9	%		November 1, 2021
			4.70% Notes	698,987				698,871				4.7	%		March 15, 2022
			3.50% Notes	993,230				992,520				3.5	%		January 31, 2023
			5.00% Notes	1,010,834				499,455				5	%		February 15, 2024
		Total American Tower Corporation debt		10,550,773				9,976,108
	Other debt, including capital lease obligations			95,382				73,378
			Total	14,608,708				14,478,278
	Less current portion of long-term obligations			(897,624		)		(70,132		)
			Long-term obligations	$	13,711,084			$	14,408,146
	__________
	(1) Represents the interest rate and maturity date as of December 31, 2014 and does not reflect the impact of interest rate swap agreements.
	(2) Represents anticipated repayment date.
	(3) Includes approximately $26.9 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments for debt assumed upon the acquisition of MIPT.
	(4) Denominated in Brazilian Real (“BRL”). As of December 31, 2014, the aggregate principal amount outstanding under the BR Towers Debentures and the BR Towers Credit Facility is 315.3 million BRL and 43.5 million BRL respectively. A portion of the debt accrues interest at a variable rate.
	(5) Includes approximately $7.7 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments recognized upon the acquisition of Unison Holdings, LLC and Unison Site Management II, L.L.C. (collectively, “Unison”).
	(6) Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.
	(7) Denominated in Mexican Pesos (“MXN”). As of December 31, 2014, the aggregate principal amount outstanding under the Mexican Loan is 3.9 billion MXN.
	(8) Denominated in South African Rand (“ZAR”). As of December 31, 2014, the aggregate principal amount outstanding under the South African Facility is
	869.3 million ZAR.
	(9) Denominated in Colombian Pesos (“COP”). As of December 31, 2014, the aggregate principal amount outstanding under the Colombian Credit Facility is 200.0 billion COP.
	(10) Reflects balances owed to the Company’s joint venture partners in Ghana and Uganda. The Ghana loan is denominated in Ghanaian Cedi (“GHS”) and the Uganda loan is denominated in USD.
	(11) On September 19, 2014, the Company amended and restated its $1.0 billion senior unsecured revolving credit facility as described below.
	(12) On February 11, 2015, the Company redeemed all of the outstanding 4.625% senior notes due 2015. See note 24.
Schedule of GTP securitizations	The following table sets forth certain terms of the GTP Notes:
	GTP Notes	Issue Date	Original Principal Amount	Interest Rate		Anticipated Repayment Date	Final Maturity Date
			(in thousands)
	Series 2011-1 Class C notes	March 11, 2011	$70,000	3.967	%	June 15, 2016	June 15, 2041
	Series 2011-2 Class C notes	July 7, 2011	$490,000	4.347	%	June 15, 2016	June 15, 2041
	Series 2011-2 Class F notes	July 7, 2011	$155,000	7.628	%	June 15, 2016	June 15, 2041
	Series 2012-1 Class A notes (1)	February 28, 2012	$100,000	3.721	%	March 15, 2017	March 15, 2042
	Series 2012-2 Class A notes (1)	February 28, 2012	$114,000	4.336	%	March 15, 2019	March 15, 2042
	Series 2012-2 Class B notes	February 28, 2012	$41,000	6.413	%	March 15, 2019	March 15, 2042
	Series 2012-2 Class C notes	February 28, 2012	$27,000	7.358	%	March 15, 2019	March 15, 2042
	Series 2013-1 Class C notes	April 24, 2013	$190,000	2.364	%	May 15, 2018	May 15, 2043
	Series 2013-1 Class F notes	April 24, 2013	$55,000	4.704	%	May 15, 2018	May 15, 2043
	__________
	(1) Does not reflect MIPT’s repayment of approximately $1.4 million aggregate principal amount prior to the date of acquisition and the Company’s repayment of approximately $3.5 million aggregate principal amount after the date of acquisition in accordance with the repayment schedules.
Schedule of BR Towers credit facility sublimits	The BR Towers Credit Facility consists of three sublimits, the material terms of which are as follows:
			Maximum Borrowing Amount		Maturity Date		Interest Rate as of
			(BRL, in millions)				31-Dec-14
	Sublimit A		20.2 BRL ($7.6 USD)		15-Jul-20		10.8	%	-1
	Sublimit B		27.6 BRL ($10.4 USD)		15-Jan-22		3.5	%
	Sublimit C		0.2 BRL ($0.1 USD)		15-Jul-20		5.9	%	-1
	(1) Sublimit A and Sublimit C accrue interest at a per annum rate equal to 4.80% plus 1.00% and 0.90%, respectively, above the Long-Term Interest Rates disclosed by the Central Bank of Brazil (the “LTIR”). If the LTIR exceeds 6.00%, the amount of interest payable on the portion of the LTIR exceeding 6.00% will be capitalized in a manner pursuant to the terms of the loan agreement.
Schedule of shareholder loans	Outstanding amounts under each of the Company’s shareholder loans consist of the following as of December 31, (in thousands):
		2014			2013			Contractual Interest Rate			Maturity Date
	2014 Ghana Loan(1)(2)	68,651			—			21.87	%		December 31, 2019
	Uganda Loan(3)(4)	69,004			66,926			5.842	%		June 29, 2019
	Ghana Loan(2)	—			158,327			N/A			N/A
	(1)     Denominated in GHS. As of December 31, 2014, the aggregate principal amount outstanding under the 2014 Ghana Loan is 220.9 million GHS.
	(2)     During the year ended December 31, 2014, the joint venture in Ghana converted $175.2 million of existing notes under the U.S. Dollar-denominated
	Ghana Loan into a new 220.9 million GHS (approximately $68.7 million) denominated shareholder loan. The remaining balance of the Ghana Loan was
	converted into equity of the respective holders.
	(3)     Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.
	(4)     Includes approximately $2.1 million of capitalized accrued interest pursuant to the terms of the loan agreement.
Schedule of debt discounts	The following table outlines key terms related to the Company’s outstanding senior notes as of December 31, 2014:
						Unamortized (Discount) Premium
		Aggregate Principal Amount				2014				2013				Semi-annual interest		Issue Date	Maturity Date
														payments due
		(in thousands)
	4.625% Notes	$	600,000			$	(42	)		$	(206	)		April 1 and October 1		20-Oct-09	April 1, 2015
	7.00% Notes	500,000				—				—				April 15 and October 15		1-Oct-07	October 15, 2017
	4.50% Notes	1,000,000				(369		)		(480		)		January 15 and July 15		7-Dec-10	January 15, 2018
	3.40 % Notes (1)	1,000,000				5,509				(627		)		February 15 and August 15		19-Aug-13	February 15, 2019
	7.25% Notes	300,000				(2,740		)		(3,252		)		May 15 and November 15		10-Jun-09	May 15, 2019
	5.05% Notes	700,000				(504		)		(587		)		March 1 and September 1		16-Aug-10	September 1, 2020
	3.450% Notes	650,000				(3,606		)		—				March 15 and September 15		7-Aug-14	September 15, 2021
	5.90% Notes	500,000				(526		)		(586		)		May 1 and November 1		6-Oct-11	November 1, 2021
	4.70% Notes	700,000				(1,013		)		(1,129		)		March 15 and September 15		12-Mar-12	March 15, 2022
	3.50% Notes	1,000,000				(6,770		)		(7,480		)		January 31 and July 31		8-Jan-13	January 31, 2023
	5.00% Notes (1)	1,000,000				10,834				(545		)		February 15 and August 15		19-Aug-13	February 15, 2024
	__________
	(1) The original issue date for the 3.40% Notes and the 5.00% Notes was August 19, 2013. The issue date for the reopened 3.40% Notes and the reopened 5.00% Notes was January 10, 2014.
Aggregate carrying value of long-term debt, including capital leases	As of December 31, 2014, aggregate principal maturities of long-term debt, including capital leases, for the next five years and thereafter are expected to be (in thousands):
	Year Ending December 31,
	2015	$	897,624
	2016	758,054
	2017	706,488
	2018	1,793,100
	2019	3,163,859
	Thereafter	7,254,208
	Total cash obligations	14,573,333
	Unamortized discounts and premiums, net	35,375
	Balance as of December 31, 2014	$	14,608,708

Other_NonCurrent_Liabilities_T

Other Non-Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Other Liabilities, Noncurrent [Abstract]
Other non-current liabilities	Other non-current liabilities consists of the following as of December 31, (in thousands):
		2014		2013 (1)
	Unearned revenue	$	415,809	$	278,295
	Deferred rent liability	303,442		273,318
	Other miscellaneous liabilities	309,131		251,655
	Balance as of December 31,	$	1,028,382	$	803,268
	__________
	-1	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation [Abstract]
Carrying value of asset retirement obligations	The changes in the carrying amount of the Company’s asset retirement obligations are as follows (in thousands):
		2014			2013 (1)
	Beginning balance as of January 1,	$	549,548		$	435,624
	Additions	52,623			117,330
	Accretion expense	40,325			34,045
	Revisions in estimates (2)	(32,311		)	(36,492		)
	Settlements	(1,150		)	(959		)
	Balance as of December 31,	$	609,035		$	549,548
	__________
	-1	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
	-2	Revisions in estimates include the impact of approximately $(38.5) million and $(19.8) million of foreign currency translation for the years ended December 31, 2014 and 2013, respectively.

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 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):
		31-Dec-14					31-Dec-13
		Local		USD			Local		USD
	South Africa (ZAR)
	Notional	440,614		38,080			469,354		44,732
	Fair Value	1,016		88			939		90
	Colombia (COP)
	Notional	100,000,000		41,798			101,250,000		52,547
	Fair Value	(1,548,688	)	(647	)		(3,000,236	)	(1,557	)
	Costa Rica (USD) (1)
	Notional	—		—			N/A		42,000
	Fair Value	—		—			N/A		(628	)
	__________
	(1) One of the Company’s Costa Rican subsidiaries had three interest rate swap agreements, which were terminated upon repayment of the Costa Rica Loan in February 2014.
Schedule of interest rate swap agreements' impact on other comprehensive income	During the years ended December 31, 2014, 2013 and 2012, the interest rate swap agreements and treasury rate lock had the following impact on the Company’s consolidated financial statements (in thousands):
	Year Ended December 31,	Gain(Loss) Recognized in OCI - Effective Portion		Gain(Loss)		Location of Gain(Loss) Reclassified from AOCI into Income- Effective Portion (1)		Gain(Loss) Recognized		Location of Gain(Loss) Recognized in Income -
				Reclassified from				in Income - Ineffective Portion		Ineffective Portion
				AOCI into
				Income -
				Effective Portion
	2014	($2,082)		($3,606)		Interest expense/Loss on retirement of long-term obligations		N/A		N/A
	2013	$1,481		($2,809)		Interest expense		N/A		N/A
	2012	($6,220)		($1,340)		Interest expense		N/A		N/A
	__________
	(1) During the year ended December 31, 2014, amount includes $1.0 million reclassified from AOCI into Loss on retirement of long-term obligations in connection with the settlement of the interest rate swap related to the Colombian Long-Term Credit Facility.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Schedule of fair value	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):
			December 31, 2014
			Fair Value Measurements Using								Assets/Liabilities
			Level 1		Level 2				Level 3		at Fair Value
	Assets:
	Short-term investments (1)				$	6,302					$	6,302
	Interest rate swap agreements				$	88					$	88
	Liabilities:
	Acquisition-related contingent consideration								$	28,524	$	28,524
	Interest rate swap agreements				$	647					$	647
			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 contingent consideration changes	During the years ended December 31, 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	6,412				13,474
	Settlements	(3,889		)		(8,789		)
	Change in fair value	(225		)		5,743
	Foreign currency translation adjustment	(4,934		)		(2,249		)
	Other (1)	(730		)		—
	Balance as of December 31	$	28,524			$	31,890
	__________
	(1) In connection with the sale of operations in Panama, the buyer assumed the Company’s potential obligations related to additional purchase price
	consideration.

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Schedule of accumulated other comprehensive income (loss)	The changes in Accumulated other comprehensive loss for the years ended December 31, 2014 and 2013, are as follows (in thousands):
		Unrealized Losses on Cash Flow Hedges			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 before reclassifications, net of tax	(1,966		)	—			(484,323		)	(486,289		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	2,490			798			—			3,288
	Net current-period other comprehensive income (loss)	524			798			(484,323		)	(483,001		)
	Balance as of December 31, 2014	$	(1,345	)	$	(2,231	)	$	(790,645	)	$	(794,221	)
		Unrealized Losses on Cash Flow Hedges			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	867			—			(131,160		)	(130,293		)
	Amounts reclassified from accumulated other comprehensive loss, net of tax	1,622			798			—			2,420
	Net current-period other comprehensive income (loss)	2,489			798			(131,160		)	(127,873		)
	Balance as of December 31, 2013	$	(1,869	)	$	(3,029	)	$	(306,322	)	$	(311,220	)

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax provision from continuing operations	The income tax provision from continuing operations is comprised of the following for the years ended December 31, (in thousands):
		2014				2013				2012
	Current:
	Federal	$	(2,390	)		$	(30,322	)		$	(18,170	)
	State	(797		)		(13,731		)		(6,321		)
	Foreign	(57,934		)		(44,973		)		(53,513		)
	Deferred:
	Federal	(4,180		)		(16,318		)		(13,094		)
	State	(973		)		(5,139		)		(666		)
	Foreign	3,769				50,942				(15,540		)
	Income tax provision	$	(62,505	)		$	(59,541	)		$	(107,304	)
Components of income from continuing operations before income taxes and income on equity method investments	The domestic and foreign components of income from continuing operations before income taxes and income on equity method investments are as follows for the years ended December 31, (in thousands):
		2014				2013				2012
	United States	$	857,457			$	766,772			$	787,960
	Foreign	8,247				(225,023		)		(86,666		)
	Total	$	865,704			$	541,749			$	701,294
Reconciliation between the U.S. statutory rate and the effective rate from continuing operations	Reconciliation between the U.S. statutory rate and the effective rate from continuing operations is as follows for the years ended December 31:
		2014			2013			2012
	Statutory tax rate	35	%		35	%		35	%
	Tax adjustment related to REIT (1)	(35	)		(35	)		(35	)
	State taxes, net of federal benefit	1			3			1
	Foreign taxes	2			(5	)		4
	Foreign withholding taxes	3			6			4
	Domestic TRS restructuring	—			4			—
	Change in valuation allowance	—			—			8
	Other	1			3			(2	)
	Effective tax rate	7	%		11	%		15	%
	__________
	(1) Includes 24%, 28% and 18% from dividend paid deductions in 2014, 2013 and 2012, respectively.
Components of the net deferred tax asset and related valuation allowance	The components of the net deferred tax asset and related valuation allowance are as follows as of December 31, (in thousands):
		2014				2013 (1)
	Current assets:
	Allowances, accruals and other items not currently deductible	$	20,525			$	28,077
	Current deferred liabilities	(2,799		)		(4,547		)
	Subtotal	17,726				23,530
	Valuation allowance	(3,094		)		(3,638		)
	Net current deferred tax assets	$	14,632			$	19,892
	Non-current items:
	Assets:
	Net operating loss carryforwards	242,701				197,335
	Accrued asset retirement obligations	103,975				88,884
	Stock-based compensation	693				4,331
	Unearned revenue	18,947				46,788
	Unrealized loss on foreign currency	15,952				68,951
	Items not currently deductible and other	22,142				23,908
	Liabilities:
	Depreciation and amortization	(132,254		)		(82,068		)
	Deferred rent	(18,355		)		(17,814		)
	Other	(1,805		)		(5,302		)
	Subtotal	251,996				325,013
	Valuation allowance	(138,147		)		(132,368		)
	Net non-current deferred tax assets	$	113,849			$	192,645
	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
Net operating loss carryforwards expire	If not utilized, the Company’s net operating loss carryforwards expire as follows (in thousands):
	Years ended December 31,	Federal				State				Foreign
	2015 to 2019	$	—			$	82,656			$	11,896
	2020 to 2024	—				290,466				163,078
	2025 to 2029	510,016				444,038				—
	2030 to 2034	429,759				217,367				—
	Indefinite carryforward	—				—				648,731
	Total	$	939,775			$	1,034,527			$	823,705
Change in unrecognized tax benefit	A reconciliation of the beginning and ending amount of unrecognized tax benefits are as follows for the years ended December 31, (in thousands):
		2014				2013				2012
	Balance at January 1	$	32,545			$	34,337			$	38,886
	Additions based on tax positions related to the current year	4,187				1,427				1,037
	Additions for tax positions of prior years	3,780				—				—
	Reductions for tax positions of prior years	—				(320		)		(221		)
	Foreign currency	(3,216		)		(1,681		)		(439		)
	Reduction as a result of the lapse of statute of limitations and effective settlements (1)	(5,349		)		(1,218		)		(4,926		)
	Balance at December 31	$	31,947			$	32,545			$	34,337
	(1) Includes $2.1 million of effective settlements for the year ended December 31, 2012.

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Assumptions used to determine the grant date fair value for options granted	Key assumptions used to apply this pricing model are as follows:
		2014		2013		2012
	Range of risk-free interest rate	1.46% - 1.74%		0.75% - 1.42%		0.62% - 1.03%
	Weighted average risk-free interest rate	1.64%		0.91%		0.92%
	Expected life of option grants	4.5 years		4.4 years		4.4 years
	Range of expected volatility of the underlying stock price	21.94% - 23.35%		24.43% - 36.09%		36.53% - 37.86%
	Weighted average expected volatility of underlying stock price	23.08%		33.37%		37.84%
	Expected annual dividend yield	1.50%		1.50%		1.50%
Summary of the company's option activity	The Company’s option activity for the year ended December 31, 2014 is as follows:
			Options			Weighted			Weighted		Aggregate
						Average			Average		Intrinsic Value
						Exercise Price			Remaining		(in millions)
									Life (Years)
	Outstanding as of January 1, 2014		6,106,171			$	52.81
	Granted		1,879,594			81.32
	Exercised		(1,267,320	)		44.63
	Forfeited		(176,522	)		74.8
	Expired		(33,488	)		33.46
	Outstanding as of December 31, 2014		6,508,435			$	62.14		6.77		$	238.9
	Exercisable as of December 31, 2014		2,992,252			$	46.77		4.84		$	155.8
	Vested or expected to vest as of December 31, 2014		6,506,185			$	62.13		6.77		$	238.9
Schedule of options outstanding	The following table sets forth information regarding options outstanding at December 31, 2014:
	Options Outstanding							Options Exercisable
	Outstanding		Range of Exercise		Weighted		Weighted Average	Options		Weighted
	Number of		Price Per Share		Average Exercise		Remaining Life	Exercisable		Average Exercise
	Options				Price Per Share		(Years)			Price Per Share
	1,553,717		$18.60 - $43.11		$36.04		3.54	1,553,717		$36.04
	971,207		44.92 - 58.60		49.25		5.2	744,434		48.63
	954,608		62.00 - 74.06		62.52		7.24	397,291		62.3
	1,232,856		76.90 - 79.45		76.95		8.2	256,378		76.92
	1,796,047		81.18 - 93.45		81.32		9.2	40,432		81.18
	6,508,435		$18.60 - $93.45		$62.14		6.77	2,992,252		$46.77
Summary of the company's restricted stock unit activity	The Company’s restricted stock unit activity during the year ended December 31, 2014 is as follows:
		Number of			Weighted Average Grant
		Units			Date Fair Value
	Outstanding as of January 1, 2014	1,840,137			$	64.75
	Granted	807,582			81.54
	Vested	(716,905	)		59.65
	Forfeited	(171,997	)		72.36
	Outstanding as of December 31, 2014	1,758,817			$	73.8
	Expected to vest, net of estimated forfeitures, as of December 31, 2014	1,685,937			$	73.59
Schedule of employee stock purchase plan valuation assumptions	Key assumptions used to apply the Black-Scholes pricing model for shares purchased through the ESPP for the years ended December 31, are as follows:
		2014		2013		2012
	Range of risk-free interest rate	0.06% - 0.11%		0.07% – 0.13%		0.05% – 0.12%
	Weighted average risk-free interest rate	0.09%		0.10%		0.08%
	Expected life of shares	6 months		6 months		6 months
	Range of expected volatility of underlying stock price over the option period	11.29% – 16.59%		12.21% – 13.57%		33.16% – 33.86%
	Weighted average expected volatility of underlying stock price	14.14%		12.88%		33.54%
	Expected annual dividend yield	1.50%		1.50%		1.50%

Equity_Tables

Equity (Tables)	12 Months Ended
	Dec. 31, 2014
Preferred Stock
Dividends Paid [Line Items]
Schedule of Stock by Class
			For the year ended December 31,
			2014					2013 (2)				2012 (2)
			Per Share			%		Per Share		%		Per Share		%
	Preferred Stock
		Ordinary income	$	2.6688		100	%	$	—	—	%	$	—	—	%
		Capital gain	—			—		—		—		—		—
		Return of capital	—			—		—		—		—		—
		Total	$	2.6688	-1	100	%	$	—	—	%	$	—	—	%
	__________
	(1) In addition to the dividends disclosed above, on December 2, 2014, the Company declared a dividend of $1.3125 per share, payable on February 16, 2015 to
	preferred stockholders of record at the close of business on February 1, 2015.
	(2) The Company had no preferred stock outstanding during the years ended December 31, 2013 and 2012.
Common Stock
Dividends Paid [Line Items]
Schedule of Stock by Class	The following tables characterize the tax treatment of distributions declared per share of common stock and preferred stock.
			For the year ended December 31,
			2014					2013				2012
			Per Share			%		Per Share		%		Per Share		%
	Common Stock
		Ordinary income	$	1.4		100	%	$	1.1	100	%	$	0.9	100	%
		Capital gain	—			—		—		—		—		—
		Return of capital	—			—		—		—		—		—
		Total	$	1.4		100	%	$	1.1	100	%	$	0.9	100	%

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 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 years ended December 31, 2014, 2013 and 2012 (in thousands, except per share data):
		2014				2013			2012
	Net income attributable to American Tower Corporation stockholders	$	824,910			$	551,333		$	637,283
	Dividends declared on preferred stock	(23,888		)		—			—
	Net income attributable to American Tower Corporation common stockholders	801,022				551,333			637,283
	Basic weighted average common shares outstanding	395,958				395,040			394,772
	Dilutive securities	4,128				4,106			4,515
	Diluted weighted average common shares outstanding	400,086				399,146			399,287
	Basic net income attributable to American Tower Corporation common stockholders per common share	$	2.02			$	1.4		$	1.61
	Diluted net income attributable to American Tower Corporation common stockholders per common share	$	2			$	1.38		$	1.6
Schedule of antidilutive securities excluded from computation of earnings per share	The following shares were not included in the computation of diluted earnings per share for the years ended December 31, 2014, 2013 and 2012 because the effect would be anti-dilutive (in thousands, on a weighted average basis):
		2014			2013			2012
	Restricted stock awards	5			—			2
	Stock options	1,290			1,161			981
	Preferred stock (1)	4,303			—			—
	__________
	(1) Issued on May 12, 2014.

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Future minimum rental payments under non-cancelable operating leases	Such payments at December 31, 2014 are as follows (in thousands):
	Year Ending December 31,
	2015	$	574,438
	2016	553,864
	2017	538,405
	2018	519,034
	2019	502,847
	Thereafter	4,214,600
	Total	$	6,903,188
Future minimum payments under capital leases	Future minimum payments under capital leases in effect at December 31, 2014 are as follows (in thousands):
	Year Ending December 31,
	2015	$	15,589
	2016	14,049
	2017	12,905
	2018	12,456
	2019	10,760
	Thereafter	173,313
	Total minimum lease payments	239,072
	Less amounts representing interest	(143,690		)
	Present value of capital lease obligations	$	95,382
Future minimum rental receipts under operating lease agreements	Future minimum rental receipts expected from tenants under non-cancellable operating lease agreements in effect at December 31, 2014 are as follows (in thousands):
	Year Ending December 31,
	2015	$	3,438,474
	2016	3,358,098
	2017	3,304,255
	2018	3,168,551
	2019	2,916,750
	Thereafter	10,495,554
	Total	$	26,681,682

Supplemental_Cash_Flow_Informa1

Supplemental Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2014
Supplemental Cash Flow Information [Abstract]
Supplemental cash flow information and non-cash investing and financing activities	Supplemental cash flow information and non-cash investing and financing activities for the years ended December 31, 2014, 2013 and 2012 are as follows (in thousands):
		2014		2013		2012
	Supplemental cash flow information:
	Cash paid for interest	$	548,089	$	397,366	$	366,458
	Cash paid for income taxes (net of refunds of $8,476, $19,701 and $20,847, respectively)	69,212		51,676		69,277
	Non-cash investing and financing activities:
	Increase (decrease) in accounts payable and accrued expenses for purchases of property and equipment and construction activities	1,121		9,147		(10,244		)
	Purchases of property and equipment under capital leases	36,486		27,416		19,219
	Fair value of debt assumed through acquisitions	463,135		1,576,186		—
	Settlement of accounts receivable related to acquisitions	31,849		—		—
	Conversion of third-party debt to equity	111,181		—		—

Business_Segments_Tables

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting, Measurement Disclosures [Abstract]
Summarized financial information concerning the company's reportable segments	Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2014, 2013 and 2012 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; Gain (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 and income on equity method investments, as the amounts are not utilized in assessing each segment’s performance.
			Rental and Management								Total Rental and		Network		Other		Total
											Management		Development
	Year ended December 31, 2014		Domestic				International						Services
			(in thousands)
	Segment revenues		$	2,639,790			$	1,367,064			$	4,006,854	$	93,194			$	4,100,048
	Segment operating expenses (1)		515,742				539,038				1,054,780		37,648				1,092,428
	Interest income, TV Azteca, net		—				10,547				10,547		—				10,547
	Segment gross margin		2,124,048				838,573				2,962,621		55,546				3,018,167
	Segment selling, general, administrative and development expense (1)		124,944				133,978				258,922		12,469				271,391
	Segment operating profit		$	1,999,104			$	704,595			$	2,703,699	$	43,077			$	2,746,776
	Stock-based compensation expense														$	80,153	80,153
	Other selling, general, administrative and development expense														96,835		96,835
	Depreciation, amortization and accretion														1,003,802		1,003,802
	Other expense (principally interest expense and other expense)														700,282		700,282
	Income from continuing operations before income taxes and income on equity method investments																$	865,704
	Capital expenditures		$	576,153			$	374,105			$	950,258	$	—	$	24,146	$	974,404
	__________
	(1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of
	$1.8 million and $78.3 million, respectively.
			Rental and Management								Total Rental and		Network		Other		Total
											Management		Development
	Year ended December 31, 2012		Domestic				International						Services
			(in thousands)
	Segment revenues		$	1,940,689			$	862,801			$	2,803,490	$	72,470			$	2,875,960
	Segment operating expenses (1)		357,555				328,333				685,888		34,830				720,718
	Interest income, TV Azteca, net		—				14,258				14,258		—				14,258
	Segment gross margin		1,583,134				548,726				2,131,860		37,640				2,169,500
	Segment selling, general, administrative and development expense (1)		85,663				95,579				181,242		6,744				187,986
	Segment operating profit		$	1,497,471			$	453,147			$	1,950,618	$	30,896			$	1,981,514
	Stock-based compensation expense														$	51,983	51,983
	Other selling, general, administrative and development expense														89,093		89,093
	Depreciation, amortization and accretion														644,276		644,276
	Other expense (principally interest expense and other expense)														494,868		494,868
	Income from continuing operations before income taxes and income on equity method investments																$	701,294
	Capital expenditures		$	268,997			$	279,004			$	548,001	$	—	$	20,047	$	568,048
	__________
	(1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of
	$1.8 million and $50.2 million, respectively.
			Rental and Management								Total Rental and		Network		Other		Total
											Management		Development
	Year ended December 31, 2013		Domestic				International						Services
			(in thousands)
	Segment revenues		$	2,189,365			$	1,097,725			$	3,287,090	$	74,317			$	3,361,407
	Segment operating expenses (1)		405,419				422,346				827,765		30,564				858,329
	Interest income, TV Azteca, net		—				22,235				22,235		—				22,235
	Segment gross margin		1,783,946				697,614				2,481,560		43,753				2,525,313
	Segment selling, general, administrative and development expense (1)		103,989				123,338				227,327		9,257				236,584
	Segment operating profit		$	1,679,957			$	574,276			$	2,254,233	$	34,496			$	2,288,729
	Stock-based compensation expense														$	68,138	68,138
	Other selling, general, administrative and development expense														112,367		112,367
	Depreciation, amortization and accretion														800,145		800,145
	Other expense (principally interest expense and other expense)														766,330		766,330
	Income from continuing operations before income taxes and income on equity method investments																$	541,749
	Capital expenditures		$	416,239			$	277,910			$	694,149	$	—	$	30,383	$	724,532
	__________
	(1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of
	$1.5 million and $66.6 million, respectively.
Reconciliation of assets from segments to consolidated	Additional information relating to the total assets of the Company’s operating segments for the years ended December 31, is as follows (in thousands):
		2014				2013 (1)				2012
	Domestic rental and management	$	14,348,892			$	13,628,137			$	8,471,169
	International rental and management (2)	6,776,013				6,428,438				5,190,987
	Network development services	57,367				47,607				63,956
	Other (3)	149,273				179,483				363,317
	Total assets	$	21,331,545			$	20,283,665			$	14,089,429
	__________
	(1) Balances have been revised to reflect purchase accounting measurement period adjustments.
	(2) Balances are translated at the applicable period end exchange rate and therefore may impact comparability between periods.
	(3) Balances include corporate assets such as cash and cash equivalents, certain tangible and intangible assets and income tax accounts which have not been
	allocated to specific segments.
Schedule of revenue from external customers attributed to foreign countries by geographic area	Summarized geographic information related to the Company’s operating revenues for the years ended December 31, 2014, 2013 and 2012 and long-lived assets as of December 31, 2014 and 2013, is as follows (in thousands):
		2014				2013				2012
	Operating Revenues:
	United States	$	2,732,984			$	2,263,682			$	2,013,159
	International (1):
	Brazil	331,089				212,201				198,068
	Chile	31,756				28,978				22,114
	Colombia	89,421				70,901				48,424
	Costa Rica	16,742				4,055				—
	Germany	64,946				62,756				4,030
	Ghana	95,486				92,114				81,818
	India	219,566				191,355				181,863
	Mexico	354,116				288,306				217,473
	Panama (2)	1,243				424				—
	Peru	8,078				5,824				5,310
	South Africa	98,334				91,906				80,202
	Uganda	56,287				48,905				23,499
	Total international	1,367,064				1,097,725				862,801
	Total operating revenues	$	4,100,048			$	3,361,407			$	2,875,960
	__________
	(1) Balances are translated at the applicable exchange rate and therefore may impact comparability between periods.
	(2) In September 2014, the Company completed the sale of the operations in Panama.
Schedule of disclosure on geographic areas, long-lived assets
		2014				2013 (1)
	Long-Lived Assets (2):
	United States	$	12,843,271			$	12,345,357
	International (3):
	Brazil	2,162,698				1,286,490
	Chile	147,413				167,318
	Colombia	320,355				390,197
	Costa Rica	127,436				129,229
	Germany	456,698				535,883
	Ghana	235,523				304,603
	India	616,266				610,744
	Mexico	1,189,854				1,348,987
	Panama (4)	—				17,177
	Peru	61,490				58,220
	South Africa	186,270				213,316
	Uganda	185,956				195,128
	Total international	5,689,959				5,257,292
	Total long-lived assets	$	18,533,230			$	17,602,649
	__________
	(1) Balances have been revised to reflect purchase accounting measurement period adjustments.
	(2) Includes Property and equipment, net, Goodwill and Other intangible assets, net.
	(3) Balances are translated at the applicable period end exchange rate and therefore may impact comparability between periods.
	(4) In September 2014, the Company completed the sale of the operations in Panama.
Schedule of revenue by major customers	The following tenants within the domestic and international rental and management segments and network development services segment individually accounted for 10% or more of the Company’s consolidated operating revenues for the years ended December 31, 2014, 2013 and 2012 is as follows:
		2014			2013			2012
	AT&T Mobility	20	%		18	%		18	%
	Sprint Nextel	15	%		16	%		14	%
	Verizon Wireless	11	%		11	%		11	%
	T-Mobile	10	%		11	%		8	%

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2014
Selected Quarterly Financial Information [Abstract]
Schedule of quarterly financial information	Selected quarterly financial data for the years ended December 31, 2014 and 2013 is as follows (in thousands, except per share data):
		Three Months Ended											Year Ended
		March 31,		June 30,			September 30,			December 31,			December 31,
	2014:00:00
	Operating revenues	$	984,089	$	1,031,457		$	1,038,188		$	1,046,314		$	4,100,048
	Cost of operations (1)	260,769		272,275			284,202			277,019			1,094,265
	Operating income	353,637		402,499			384,807			345,979			1,486,922
	Net income	193,313		221,659			206,630			181,597			803,199
	Net income attributable to American Tower Corporation stockholders	202,499		234,431			207,593			180,387			824,910
	Dividends declared on preferred stock	—		(4,375		)	(7,700		)	(11,813		)	(23,888		)
	Net income attributable to American Tower Corporation common stockholders	202,499		230,056			199,893			168,574			801,022
	Basic net income attributable to American Tower Corporation common stockholders	0.51		0.58			0.5			0.43			2.02
	Diluted net income attributable to American Tower Corporation common stockholders	0.51		0.58			0.5			0.42			2
		Three Months Ended											Year Ended
		March 31,		June 30,			September 30,			December 31,			December 31,
	2013:00:00
	Operating revenues	$	802,728	$	808,830		$	807,880		$	941,969		$	3,361,407
	Cost of operations (1)	201,766		205,709			200,829			251,569			859,873
	Operating income	299,686		312,812			308,879			292,928			1,214,305
	Net income	160,948		84,113			163,222			73,925			482,208
	Net income attributable to American Tower Corporation stockholders	171,407		99,821			180,123			99,982			551,333
	Dividends declared on preferred stock	—		—			—			—			—
	Net income attributable to American Tower Corporation common stockholders	171,407		99,821			180,123			99,982			551,333
	Basic net income attributable to American Tower Corporation common stockholders	0.43		0.25			0.46			0.25			1.4
	Diluted net income attributable to American Tower Corporation common stockholders	0.43		0.25			0.45			0.25			1.38
	__________
	(1) Represents Operating expenses, exclusive of Depreciation, amortization and accretion, Selling, general, administrative and development expense, and Other operating expense.

Business_and_Summary_of_Signif3

Business and Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	0 Months Ended	12 Months Ended
	Dec. 02, 2014	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Dividends Paid [Line Items]
Number of customers, concentration of credit risk		4
Labor costs capitalized		$48,500,000		$44,100,000		$41,600,000
Interest costs capitalized		2,800,000		1,800,000		1,900,000
Distributions paid on common stock		-404,631,000		-434,687,000		-355,574,000
Cash distribution per share		$1.40		$1.10		$0.90
Dividends, Preferred Stock, Cash		23,888,000		0		0
Payments of ordinary dividends, preferred stock		16,013,000		0		0
Straight line revenue		123,700,000		147,700,000		165,800,000
Straight-line ground rent expense		38,400,000		29,700,000		33,700,000
Employers percentage of employees first 6 percent		75.00%				50.00%
Employee maximum annual contribution eligible for match		6.00%				6.00%
Company's contribution		6,500,000		6,000,000		4,400,000
Minimum
Dividends Paid [Line Items]
Estimated useful life of respective assets		3 years
Maximum
Dividends Paid [Line Items]
Estimated useful life of respective assets		20 years
Dividends Declared and Paid
Dividends Paid [Line Items]
Distributions paid on common stock		-554,600,000		-434,500,000		-355,600,000
Employee Stock Option
Dividends Paid [Line Items]
Vesting period		4 years
Customer Concentration Risk
Dividends Paid [Line Items]
Concentration Risk, Percentage		10.00%		10.00%		10.00%
Sales Revenue, Net | Customer Concentration Risk
Dividends Paid [Line Items]
Concentration Risk, Percentage		56.00%
Convertible Preferred Stock Subject to Mandatory Redemption | Preferred Stock
Dividends Paid [Line Items]
Dividends, Preferred Stock, Cash		$23,900,000
Preferred stock, dividends per share, cash paid		$3.98
Preferred stock, dividends per share, declared	$1.31	$2.67	[1]	$0	[2]	$0	[2]
[1]	In addition to the dividends disclosed above, on December 2, 2014, the Company declared a dividend of $1.3125 per share, payable on February 16, 2015 to preferred stockholders of record at the close of business on February 1, 2015.
[2]	The Company had no preferred stock outstanding during the years ended December 31, 2013 and 2012.

Business_and_Summary_of_Signif4

Business and Summary of Significant Accounting Policies (Changes in Allowances) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Gain (Loss) on Investments [Line Items]
Foreign currency transaction gain (loss), in AOCI and Income Statement	$468,600
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance as of January 1	19,895	20,406	24,412
Current year increases	8,243	7,025	8,028
Write-offs, net of recoveries and other	-10,832	-7,536	-12,034
Balance as of December 31	17,306	19,895	20,406
Reclassified to AOCI
Gain (Loss) on Investments [Line Items]
Foreign currency transaction gain (loss), reclassified as AOCI	419,300
Other Expense [Member]
Gain (Loss) on Investments [Line Items]
Unrealized foreign currency (losses) gains	$49,319	$211,722	$34,330

Prepaid_and_Other_Current_Asse1

Prepaid and Other Current Assets (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid operating ground leases	$88,508	$96,881	[1]
Prepaid income tax	34,512	52,612	[1]
Unbilled receivables	25,352	25,412	[1]
Prepaid assets	23,848	34,243	[1]
Value added tax receivable	23,228	77,016	[1]
Other miscellaneous current assets	59,174	61,253	[1]
Balance as of December 31,	$254,622	$347,417	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Property_and_Equipment_Narrati

Property and Equipment (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Abstract]
Depreciation expense	$551.80	$483.60	$411.90
Capital leases, which are primarily classified as towers or land and improvements	$1,111.60	$839

Property_and_Equipment_Propert

Property and Equipment (Property and Equipment) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Towers	8,300,387		$7,933,917	[1]
Equipment	995,667		762,738	[1]
Buildings and improvements	618,889		607,540	[1]
Land and improvements	1,566,096	[2]	1,369,969	[1],[2]
Construction-in-progress	214,760		170,292	[1]
Total	11,695,799		10,844,456	[1]
Less accumulated depreciation and amortization	-4,068,982		-3,666,728	[1]
Property and equipment, net	7,626,817		$7,177,728	[1]
Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years
Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Tower | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years	[3]
Tower | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	0 years	[3]
Equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	15 years	[3]
Equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years	[3]
Buildings and Improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	32 years	[3]
Buildings and Improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years	[3]
Land and Improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years	[3]
Land and Improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	0 years	[3]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Estimated useful lives apply to land improvements only.
[3]	Assets on leased land are depreciated over the shorter of the estimated useful life of the asset or the term of the corresponding ground lease taking into consideration lease renewal options and residual value.

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$411.70	$282.50	$207.30
Weighted Average
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period	15 years

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Rollforward) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Goodwill [Roll Forward]
Goodwill, beginning balance	$3,854,802	[1]	$2,842,643
Additions	217,213		1,064,577
Effect of foreign currency translation	-51,280		-52,418
Other (2)	-3,653	[2]
Goodwill, ending balance	4,017,082		3,854,802	[1]
Network Development Services
Goodwill [Roll Forward]
Goodwill, beginning balance	2,000	[1]	2,000
Additions	0		0
Effect of foreign currency translation	0		0
Other (2)	-12	[2]
Goodwill, ending balance	1,988		2,000	[1]
Domestic | Rental And Management
Goodwill [Roll Forward]
Goodwill, beginning balance	3,293,899	[1]	2,320,571
Additions	48,247		973,328
Effect of foreign currency translation	0		0
Other (2)	0	[2]
Goodwill, ending balance	3,342,146		3,293,899	[1]
Total international | Rental And Management
Goodwill [Roll Forward]
Goodwill, beginning balance	558,903	[1]	520,072
Additions	168,966		91,249
Effect of foreign currency translation	-51,280		-52,418
Other (2)	-3,641	[2]
Goodwill, ending balance	$672,948		$558,903	[1]
[1]	Balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Other represents the goodwill associated with the Company’s operations in Panama and the Company’s third-party structural analysis business. Both businesses were sold during the year ended December 31, 2014 (see note 12)

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Changes in the Carrying Value of Goodwill) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$9,161,391		$8,471,368	[1]
Accumulated Amortization	-2,347,949		-1,978,124	[1]
Net Book Value	6,813,442		6,493,244	[1]
Deferred financing costs, net	75,889	[2]	76,875	[1],[2]
Other intangible assets, net	6,889,331		6,570,119	[1]
Acquired Network Location
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	2,513,763	[3]	2,418,153	[1],[3]
Accumulated Amortization	-901,903	[3]	-791,359	[1],[3]
Net Book Value	1,611,860	[3]	1,626,794	[1],[3]
Acquired Network Location | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	0 years	[3]
Acquired Network Location | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	[3]
Acquired Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	6,579,094		6,017,849	[1]
Accumulated Amortization	-1,429,572		-1,170,239	[1]
Net Book Value	5,149,522		4,847,610	[1]
Acquired Customer Relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Acquired Customer Relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Acquired Licenses And Other Intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	43,012		6,583	[1]
Accumulated Amortization	-3,514		-2,297	[1]
Net Book Value	39,498		4,286	[1]
Acquired Licenses And Other Intangibles | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Acquired Licenses And Other Intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Economic Rights, TV Azteca
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	25,522		28,783	[1]
Accumulated Amortization	-12,960		-14,229	[1]
Net Book Value	$12,562		$14,554	[1]
Finite-Lived Intangible Asset, Useful Life	70 years
[1]	December 31, 2013 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 $)	Dec. 31, 2014
In Millions, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]
2015	$430.80
2016	424.4
2017	422.7
2018	421.8
2019	$419.90

Notes_Receivable_and_Other_Non2

Notes Receivable and Other Non-Current Assets (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2000	Dec. 31, 2014
Notes Receivable And Other NonCurrent Assets [Line Items]
Capital lease, asset	$839		1,111.60
TV Azteca
Notes Receivable And Other NonCurrent Assets [Line Items]
Loans receivable		119.8	91.8
Loan interest rate		13.11%
Term of the loan, years		70 years
Loan prepayment without penalty, period, years		50 years
Proceeds from collection of notes receivable	34.4
Interest income	2.7
Loans receivable, net of discount			82.9
Economic Rights, TV Azteca
Notes Receivable And Other NonCurrent Assets [Line Items]
Term of the loan, years		70 years
Loan prepayment without penalty, period, years			50 years
Number of broadcast towers		190
Commercial rights, annual payment		1.5
Percentage of the revenues from leasing of towers		100.00%
Capital lease, liability		18.6
Capital lease, asset		18.6
Capital lease asset and discount on note		30.2
Repayment of Principal [Member] | TV Azteca
Notes Receivable And Other NonCurrent Assets [Line Items]
Proceeds from collection of notes receivable	28
Prepayment Penalty [Member] | TV Azteca
Notes Receivable And Other NonCurrent Assets [Line Items]
Proceeds from collection of notes receivable	$4.90

Notes_Receivable_and_Other_Non3

Notes Receivable and Other Non-Current Assets (Notes Receivable and Other Non-Current Assets) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Notes Receivable And Other Long Term Assets [Abstract]
Long-term prepaid ground rent	$310,232	$217,983	[1]
Notes receivable	87,515	89,381	[1]
Other miscellaneous assets	168,707	201,809	[1]
Balance as of December 31,	$566,454	$509,173	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details)

12 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Nov. 24, 2014

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2014

Nov. 19, 2014

Oct. 01, 2013

Dec. 31, 2014

Oct. 01, 2013

Oct. 01, 2013

Dec. 31, 2014

Jan. 31, 2013

Jan. 31, 2013

Dec. 06, 2013

Aug. 08, 2013

Jun. 30, 2013

Dec. 31, 2014

Jun. 30, 2014

Dec. 06, 2013

Nov. 08, 2013

Aug. 08, 2013

Dec. 31, 2014

Nov. 08, 2013

Nov. 21, 2014

Nov. 21, 2014

Nov. 21, 2014

Nov. 29, 2013

Dec. 31, 2014

Nov. 29, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Apr. 03, 2014

Dec. 31, 2014

Apr. 03, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Aug. 31, 2014

Nov. 21, 2014

Nov. 21, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2013

Oct. 01, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Nov. 08, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

USD ($)

USD ($)

USD ($)

Airtel Acquisition

BR Towers

BR Towers

BR Towers

BR Towers

MIPT Acquisition

MIPT Acquisition

MIPT Acquisition

MIPT Acquisition

MIPT Acquisition

Axtel Mexico Acquisition

Axtel Mexico Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

TIM Acquisition

TIM Acquisition

TIM Acquisition

Z-Sites Acquisition

Z-Sites Acquisition

Z-Sites Acquisition

Other International Acquisition

Other U.S. Acquisition 2013

Ghana Acquisition

Colombia Movil Acquisition

Richland Acquisition

Richland Acquisition

Richland Acquisition

Other International Acquisitions 2014

Other International Acquisitions 2014

Other International Acquisitions 2014

Other US Acquisition 2014

GTP Notes

Secured Debt

First portfolio

Second portfolio

2014 acquisitions [Member]

2013 Acquisitions [Member]

2012 Acquisitions [Member]

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Preliminary Purchase Price Allocation

Adjusted Purchase Price Allocation

Adjusted Purchase Price Allocation

Adjusted Purchase Price Allocation

Adjusted Purchase Price Allocation

Adjusted Purchase Price Allocation

Adjusted Purchase Price Allocation

Adjusted Purchase Price Allocation

USD ($)

USD ($)

USD ($)

USD ($)

propertyinterests

USD ($)

USD ($)

Domestic

Total international

Panama (2)

USD ($)

sites

Brazil

Brazil

Brazil

Brazil

Brazil

Brazil

Mexico

Mexico

Mexico

Mexico

Brazil

Brazil

Brazil

USD ($)

USD ($)

sites

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Brazil, Ghana, Mexico, Uganda [Member]

Mexico

USD ($)

Secured Debt

GTP Notes

TIM Acquisition

TIM Acquisition

USD ($)

USD ($)

USD ($)

BR Towers

BR Towers

MIPT Acquisition

MIPT Acquisition

Axtel Mexico Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

Z-Sites Acquisition

Other International Acquisition

Other U.S. Acquisition 2013

Richland Acquisition

Other International Acquisitions 2014

Other US Acquisition 2014

MIPT Acquisition

Axtel Mexico Acquisition

NII Holdings Acquisition

NII Holdings Acquisition

Z-Sites Acquisition

Other International Acquisition

Other U.S. Acquisition 2013

sites

towers

sites

sites

USD ($)

USD ($)

sites

USD ($)

USD ($)

sites

sites

USD ($)

sites

USD ($)

USD ($)

USD ($)

BRL

BRL

sites

propertyinterests

propertyinterests

sites

USD ($)

USD ($)

propertyinterests

USD ($)

USD ($)

towers

towers

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Brazil

Mexico

Mexico

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Brazil

Mexico

USD ($)

USD ($)

USD ($)

sites

sites

sites

sites

sites

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Business Acquisition [Line Items]

Business combination, pro forma information, revenue of acquiree since acquisition date, actual

$47,000,000

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

37,600,000

Business combination, acquisition and merger related expenses

27,000,000

36,200,000

25,600,000

Business Combination, Integration Related Costs

13,100,000

1,400,000

Business Acquisition, Percentage of Voting Interests Acquired

100.00%

100.00%

Number of communications sites acquired

2,504

4,860

510

883

103

1,931

1,473

238

714

55

59

159

299

184

Number of property interests acquired

4

23

4

6

Additional communications sites to be acquired

2,113

right to use property interests acquired

43

Aggregate purchase price

1,100,000,000

568,890,000

4,858,083,000

248,500,000

349,000,000

17,700,000

341,400,000

436,000,000

427,000,000

1,100,000,000

3,000,000,000

122,800,000

123,900,000

89,800,000

65,600,000

189,400,000

68,649,000

[1]

28,300,000

180,822,000

568,900,000

189,379,000

180,820,000

Termination fee

260,000,000

Letters of credit, amount outstanding

260,000,000

Payments for Repurchase of Trust Preferred Securities

61,100,000

Noncash or part noncash acquisition, value of liabilities assumed

261,100,000

11,500,000

1,527,621,000

1,527,621,000

400,000

196,500,000

196,500,000

3,400,000

Repayments of Assumed Debt

122,100,000

Contingent consideration

28,524,000

31,890,000

23,711,000

6,500,000

6,300,000

9,300,000

Maximum number of communications sites to be acquired

4,800

2,790

1,666

5,240

1,240

Value added tax receivable

23,228,000

77,016,000

[2]

4,900,000

1,200,000

5,600,000

60,300,000

59,000,000

Fair value of net assets acquired

900,000

726,127,000

2,455,495,000

[3]

241,772,000

[4]

340,280,000

409,004,000

[5]

110,823,000

84,847,000

60,759,000

358,955,000

64,638,000

[1]

164,998,000

2,338,418,000

[6]

241,772,000

[4]

323,096,000

[1]

402,844,000

[1],[7]

110,904,000

[1]

84,847,000

[1]

60,759,000

[1]

Business acquisition, cost of acquired entity, cash paid

3,330,462,000

[8]

436,900,000

65,200,000

40,300,000

Business Combination, Consideration Transferred, Other

36,300,000

Business Combination, Partial Cash Consideration Transferred

4,000,000

Borrowings under credit facilities

2,187,000,000

3,507,000,000

2,582,000,000

2,800,000,000

Business combination, updated contingent consideration potential cash payment

2,300,000

4,100,000

600,000

19,700,000

5,900,000

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

0

0

0

0

0

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

40,400,000

4,400,000

600,000

29,500,000

5,900,000

Additional contingent consideration

6,412,000

13,474,000

100,000

6,300,000

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

1,700,000

700,000

1,400,000

Previous contingent consideration payments

3,500,000

400,000

Partial payment of aggregate purchase price

14,500,000

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

-3,379,000

-35,288,000

0

3,000,000

Short-term Debt

$250,000,000

[1]

The allocation of the purchase price was finalized during the year ended December 31, 2014.

[2]

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

[3]

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.

[4]

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

[5]

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

[6]

Balances are reflected as updated in the accompanying consolidated balance sheets as of December 31, 2013.

[7]

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

[8]

Cash consideration includes $14.5 million of an additional purchase price adjustment which was paid to the sellers during the year ended December 31, 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 $)

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

Nov. 19, 2014

Dec. 31, 2014

Apr. 03, 2014

Oct. 01, 2013

Jan. 31, 2013

Nov. 29, 2013

Dec. 31, 2013

Nov. 08, 2013

Dec. 06, 2013

Jun. 30, 2013

Dec. 31, 2012

Business Acquisition [Line Items]

Goodwill

$4,017,082,000

$3,854,802,000

[1]

$2,842,643,000

Fair value of debt assumed through acquisitions

463,135,000

1,576,186,000

0

BR Towers

Business Acquisition [Line Items]

Noncash or part noncash acquisition, value of liabilities assumed

261,100,000

11,500,000

Business Combination, Consideration Transferred

568,890,000

Other International Acquisitions 2014

Business Acquisition [Line Items]

Business Combination, Consideration Transferred

68,649,000

[2]

Richland Acquisition

Business Acquisition [Line Items]

Noncash or part noncash acquisition, value of liabilities assumed

196,500,000

196,500,000

Liabilities, Fair Value Adjustment

5,500,000

Business Combination, Consideration Transferred

189,400,000

MIPT Acquisition

Business Acquisition [Line Items]

Noncash or part noncash acquisition, value of liabilities assumed

1,527,621,000

1,527,621,000

Liabilities, Fair Value Adjustment

53,000,000

Business Combination, Consideration Transferred

4,858,083,000

Axtel Mexico Acquisition

Business Acquisition [Line Items]

Business Combination, Consideration Transferred

248,500,000

Z-Sites Acquisition

Business Acquisition [Line Items]

Business Combination, Consideration Transferred

123,900,000

122,800,000

Other International Acquisition

Business Acquisition [Line Items]

Business Combination, Consideration Transferred

89,800,000

Other U.S. Acquisition 2013

Business Acquisition [Line Items]

Noncash or part noncash acquisition, value of liabilities assumed

400,000

Business Combination, Consideration Transferred

65,600,000

Other US Acquisition 2014

Business Acquisition [Line Items]

Business Combination, Consideration Transferred

180,822,000

Preliminary Purchase Price Allocation | Other Intangible Assets [Member]

Business Acquisition [Line Items]

Finite-Lived Intangible Asset, Useful Life

11 years

Preliminary Purchase Price Allocation | BR Towers

Business Acquisition [Line Items]

Current assets

31,832,000

Non-current assets

9,135,000

Property and equipment

141,422,000

Customer-related intangible assets

495,279,000

[3]

Current liabilities

-23,930,000

Other non-current liabilities

-101,508,000

Fair value of net assets acquired

726,127,000

Goodwill

164,955,000

[4]

Fair value of net assets acquired

891,082,000

Fair value of debt assumed through acquisitions

-261,136,000

[5]

Preferred Stock Assumed Through Acquisitions

-61,056,000

Business Combination, Consideration Transferred

568,900,000

Preliminary Purchase Price Allocation | BR Towers | Other Intangible Assets [Member]

Business Acquisition [Line Items]

Other intangible assets

37,664,000

[3]

Preliminary Purchase Price Allocation | BR Towers | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

136,233,000

[3]

Preliminary Purchase Price Allocation | Other International Acquisitions 2014

Business Acquisition [Line Items]

Current assets

7,072,000

[2]

Non-current assets

1,521,000

[2]

Property and equipment

32,225,000

[2]

Customer-related intangible assets

20,217,000

[2],[3]

Current liabilities

-863,000

[2]

Other non-current liabilities

-6,263,000

[2]

Fair value of net assets acquired

64,638,000

[2]

Goodwill

4,011,000

[2],[4]

Fair value of net assets acquired

68,649,000

[2]

Fair value of debt assumed through acquisitions

0

[2],[5]

Preferred Stock Assumed Through Acquisitions

0

[2]

Preliminary Purchase Price Allocation | Other International Acquisitions 2014 | Other Intangible Assets [Member]

Business Acquisition [Line Items]

Other intangible assets

0

[2],[3]

Preliminary Purchase Price Allocation | Other International Acquisitions 2014 | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

10,729,000

[2],[3]

Preliminary Purchase Price Allocation | Richland Acquisition

Business Acquisition [Line Items]

Current assets

8,583,000

Non-current assets

0

Property and equipment

185,777,000

Customer-related intangible assets

169,452,000

[3]

Current liabilities

-3,635,000

Other non-current liabilities

-2,922,000

Fair value of net assets acquired

358,955,000

Goodwill

32,423,000

[4]

Fair value of net assets acquired

391,378,000

Fair value of debt assumed through acquisitions

-201,999,000

[5]

Preferred Stock Assumed Through Acquisitions

0

Business Combination, Consideration Transferred

189,379,000

Preliminary Purchase Price Allocation | Richland Acquisition | Other Intangible Assets [Member]

Business Acquisition [Line Items]

Other intangible assets

0

[3]

Preliminary Purchase Price Allocation | Richland Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

1,700,000

[3]

Preliminary Purchase Price Allocation | MIPT Acquisition

Business Acquisition [Line Items]

Cash and cash equivalents

35,967,000

[6]

Restricted cash

30,883,000

[6]

Accounts receivable, net

10,021,000

[6]

Prepaid and other current assets

22,875,000

[6]

Property and equipment

996,901,000

[6]

Customer-related intangible assets

2,629,188,000

[6],[7]

Notes receivable and other non-current assets

4,220,000

[6]

Accounts payable

-9,249,000

[6]

Accrued expenses

-37,004,000

[6]

Accrued interest

-3,253,000

[6]

Current portion of long-term obligations

-2,820,000

[6]

Unearned revenue

-35,753,000

[6]

Long-term obligations

-1,573,366,000

[6],[8]

Asset retirement obligations

-43,089,000

[6]

Other non-current liabilities

-37,326,000

[6]

Fair value of net assets acquired

2,455,495,000

[6]

Goodwill

874,967,000

[6],[9]

Preliminary Purchase Price Allocation | MIPT Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

467,300,000

[6],[7]

Preliminary Purchase Price Allocation | Axtel Mexico Acquisition

Business Acquisition [Line Items]

Current assets

0

[10]

Non-current assets

2,626,000

[10]

Property and equipment

86,100,000

[10]

Customer-related intangible assets

119,392,000

[10],[7]

Current liabilities

0

[10]

Other non-current liabilities

-9,377,000

[10]

Fair value of net assets acquired

241,772,000

[10]

Goodwill

6,751,000

[10],[11]

Preliminary Purchase Price Allocation | Axtel Mexico Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

43,031,000

[10],[7]

Preliminary Purchase Price Allocation | Z-Sites Acquisition

Business Acquisition [Line Items]

Current assets

0

Non-current assets

6,157,000

Property and equipment

24,832,000

Customer-related intangible assets

64,213,000

[7]

Current liabilities

0

Other non-current liabilities

-1,502,000

Fair value of net assets acquired

110,823,000

Goodwill

11,953,000

[11]

Preliminary Purchase Price Allocation | Z-Sites Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

17,123,000

[7]

Preliminary Purchase Price Allocation | Other International Acquisition

Business Acquisition [Line Items]

Current assets

4,863,000

Non-current assets

1,991,000

Property and equipment

44,844,000

Customer-related intangible assets

20,590,000

[7]

Current liabilities

0

Other non-current liabilities

-8,168,000

Fair value of net assets acquired

84,847,000

Goodwill

4,970,000

[11]

Preliminary Purchase Price Allocation | Other International Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

20,727,000

[7]

Preliminary Purchase Price Allocation | Other U.S. Acquisition 2013

Business Acquisition [Line Items]

Current assets

1,220,000

Non-current assets

44,000

Property and equipment

23,803,000

Customer-related intangible assets

29,325,000

[7]

Current liabilities

-454,000

Other non-current liabilities

-786,000

Fair value of net assets acquired

60,759,000

Goodwill

4,403,000

[11]

Preliminary Purchase Price Allocation | Other U.S. Acquisition 2013 | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

7,607,000

[7]

Preliminary Purchase Price Allocation | Other US Acquisition 2014

Business Acquisition [Line Items]

Current assets

797,000

Non-current assets

0

Property and equipment

38,413,000

Customer-related intangible assets

89,990,000

[3]

Current liabilities

-1,997,000

Other non-current liabilities

-1,675,000

Fair value of net assets acquired

164,998,000

Goodwill

15,824,000

[4]

Fair value of net assets acquired

180,822,000

Fair value of debt assumed through acquisitions

0

[5]

Preferred Stock Assumed Through Acquisitions

0

Business Combination, Consideration Transferred

180,820,000

Preliminary Purchase Price Allocation | Other US Acquisition 2014 | Other Intangible Assets [Member]

Business Acquisition [Line Items]

Other intangible assets

0

[3]

Preliminary Purchase Price Allocation | Other US Acquisition 2014 | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

39,470,000

[3]

Adjusted Purchase Price Allocation | MIPT Acquisition

Business Acquisition [Line Items]

Cash and cash equivalents

35,967,000

[12]

Restricted cash

30,883,000

[12]

Accounts receivable, net

10,102,000

[12]

Prepaid and other current assets

40,865,000

[12]

Property and equipment

910,713,000

[12]

Customer-related intangible assets

2,456,582,000

[12],[7]

Notes receivable and other non-current assets

68,388,000

[12]

Accounts payable

-9,969,000

[12]

Accrued expenses

-42,867,000

[12]

Accrued interest

-3,253,000

[12]

Current portion of long-term obligations

-2,820,000

[12]

Unearned revenue

-35,905,000

[12]

Long-term obligations

-1,573,366,000

[12],[8]

Asset retirement obligations

-57,965,000

[12]

Other non-current liabilities

-17,837,000

[12]

Fair value of net assets acquired

2,338,418,000

[12]

Goodwill

992,044,000

[12],[9]

Adjusted Purchase Price Allocation | MIPT Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

528,900,000

[12],[7]

Adjusted Purchase Price Allocation | Axtel Mexico Acquisition

Business Acquisition [Line Items]

Current assets

0

[10]

Non-current assets

2,626,000

[10]

Property and equipment

86,100,000

[10]

Customer-related intangible assets

119,392,000

[10],[7]

Current liabilities

0

[10]

Other non-current liabilities

-9,377,000

[10]

Fair value of net assets acquired

241,772,000

[10]

Goodwill

6,751,000

[10],[11]

Adjusted Purchase Price Allocation | Axtel Mexico Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

43,031,000

[10],[7]

Adjusted Purchase Price Allocation | Z-Sites Acquisition

Business Acquisition [Line Items]

Current assets

0

[2]

Non-current assets

6,718,000

[2]

Property and equipment

26,881,000

[2]

Customer-related intangible assets

62,286,000

[2],[7]

Current liabilities

0

[2]

Other non-current liabilities

-2,331,000

[2]

Fair value of net assets acquired

110,904,000

[2]

Goodwill

13,040,000

[11],[2]

Adjusted Purchase Price Allocation | Z-Sites Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

17,350,000

[2],[7]

Adjusted Purchase Price Allocation | Other International Acquisition

Business Acquisition [Line Items]

Current assets

4,863,000

[2]

Non-current assets

1,991,000

[2]

Property and equipment

44,844,000

[2]

Customer-related intangible assets

20,590,000

[2],[7]

Current liabilities

0

[2]

Other non-current liabilities

-8,168,000

[2]

Fair value of net assets acquired

84,847,000

[2]

Goodwill

4,970,000

[11],[2]

Adjusted Purchase Price Allocation | Other International Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

20,727,000

[2],[7]

Adjusted Purchase Price Allocation | Other U.S. Acquisition 2013

Business Acquisition [Line Items]

Current assets

1,220,000

[2]

Non-current assets

44,000

[2]

Property and equipment

23,537,000

[2]

Customer-related intangible assets

29,325,000

[2],[7]

Current liabilities

-454,000

[2]

Other non-current liabilities

-848,000

[2]

Fair value of net assets acquired

60,759,000

[2]

Goodwill

4,403,000

[11],[2]

Adjusted Purchase Price Allocation | Other U.S. Acquisition 2013 | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

7,935,000

[2],[7]

Mexico | Other International Acquisitions 2014

Business Acquisition [Line Items]

Noncash or part noncash acquisition, value of liabilities assumed

3,400,000

Mexico | NII Holdings Acquisition

Business Acquisition [Line Items]

Fair value of net assets acquired

900,000

Value added tax receivable, current

59,000,000

60,300,000

Business Combination, Consideration Transferred

427,000,000

436,000,000

Mexico | Preliminary Purchase Price Allocation | NII Holdings Acquisition

Business Acquisition [Line Items]

Current assets

61,183,000

[13]

Non-current assets

11,969,000

[13]

Property and equipment

147,364,000

[13]

Customer-related intangible assets

135,175,000

[13],[7]

Current liabilities

0

[13]

Other non-current liabilities

-10,478,000

[13]

Fair value of net assets acquired

409,004,000

[13]

Goodwill

27,928,000

[11],[13]

Mexico | Preliminary Purchase Price Allocation | NII Holdings Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

63,791,000

[13],[7]

Mexico | Adjusted Purchase Price Allocation | NII Holdings Acquisition

Business Acquisition [Line Items]

Current assets

59,938,000

[14],[2]

Non-current assets

10,738,000

[14],[2]

Property and equipment

143,680,000

[14],[2]

Customer-related intangible assets

132,897,000

[14],[2],[7]

Current liabilities

0

[14],[2]

Other non-current liabilities

-10,478,000

[14],[2]

Fair value of net assets acquired

402,844,000

[14],[2]

Goodwill

25,056,000

[11],[14],[2]

Mexico | Adjusted Purchase Price Allocation | NII Holdings Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

66,069,000

[14],[2],[7]

Brazil | NII Holdings Acquisition

Business Acquisition [Line Items]

Business Combination, Consideration Transferred

341,400,000

349,000,000

17,700,000

Brazil | Preliminary Purchase Price Allocation | NII Holdings Acquisition

Business Acquisition [Line Items]

Current assets

0

Non-current assets

4,484,000

Property and equipment

105,784,000

Customer-related intangible assets

149,333,000

[7]

Current liabilities

0

Other non-current liabilities

-13,188,000

Fair value of net assets acquired

340,280,000

Goodwill

8,704,000

[11]

Brazil | Preliminary Purchase Price Allocation | NII Holdings Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

93,867,000

[7]

Brazil | Adjusted Purchase Price Allocation | NII Holdings Acquisition

Business Acquisition [Line Items]

Current assets

0

[2]

Non-current assets

9,534,000

[2]

Property and equipment

109,426,000

[2]

Customer-related intangible assets

142,125,000

[2],[7]

Current liabilities

0

[2]

Other non-current liabilities

-20,100,000

[2]

Fair value of net assets acquired

323,096,000

[2]

Goodwill

18,312,000

[11],[2]

Brazil | Adjusted Purchase Price Allocation | NII Holdings Acquisition | Acquired Network Location

Business Acquisition [Line Items]

Network location intangible assets

$82,111,000

[2],[7]

Maximum | Acquired Network Location

Business Acquisition [Line Items]

Finite-Lived Intangible Asset, Useful Life

20 years

[15]

Maximum | Preliminary Purchase Price Allocation

Business Acquisition [Line Items]

Finite-Lived Intangible Asset, Useful Life

20 years

Customer-related and network location intangible assets [Member] | Maximum | Preliminary Purchase Price Allocation

Business Acquisition [Line Items]

Finite-Lived Intangible Asset, Useful Life

20 years

Customer-related and network location intangible assets [Member] | Maximum | Adjusted Purchase Price Allocation | MIPT Acquisition

Business Acquisition [Line Items]

Finite-Lived Intangible Asset, Useful Life

20 years

[1]

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

[2]

The allocation of the purchase price was finalized during the year ended December 31, 2014.

[3]

Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years. Other intangible assets are amortized on a straight-line basis over the life of the lease, which is a period of 11 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 except for goodwill associated with BR Towers where goodwill is expected to be partially deductible.

[5]

BR Towers debt assumed approximated fair value at the date of acquisition and includes $11.5 million of current indebtedness. Richland debt assumed includes $196.5 million of Richland’s 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.

[6]

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.

[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 $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.

[9]

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.

[10]

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

[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]

Balances are reflected as updated in the accompanying consolidated balance sheets as of December 31, 2013.

[13]

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

[14]

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

[15]

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.

Acquisitions_Pro_Forma_Informa

Acquisitions (Pro Forma Information) (Details) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition, Pro Forma Information [Abstract]
Pro forma operating revenues	$4,193,067	$3,848,549
Pro forma net income attributable to American Tower Corporation	$770,871	$394,253
Basic net income attributable to American Tower Corporation (in dollars per share)	$1.95	$1
Diluted net income attributable to American Tower Corporation (in dollars per share)	$1.93	$0.99

Accrued_Expenses_Details

Accrued Expenses (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accrued Liabilities, Current [Abstract]
Payroll and related withholdings	$61,206	$54,529	[1]
Accrued property and real estate taxes	57,110	50,843	[1]
Accrued construction costs	46,024	52,446	[1]
Accrued rent	34,074	28,456	[1]
Other accrued expenses	219,340	234,914	[1]
Balance as of December 31,	$417,754	$421,188	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

LongTerm_Obligations_Narrative

Long-Term Obligations (Narrative) (Details)

12 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Oct. 01, 2013

Dec. 31, 2014

Apr. 03, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Jan. 11, 2014

Jan. 10, 2014

Mar. 15, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Aug. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Oct. 02, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Sep. 20, 2014

Sep. 19, 2014

Jul. 21, 2014

Jan. 21, 2014

Sep. 19, 2014

Dec. 31, 2014

Dec. 31, 2013

Oct. 29, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Sep. 19, 2014

Dec. 31, 2014

Jan. 10, 2014

Dec. 31, 2013

Dec. 31, 2014

Jan. 10, 2014

Dec. 31, 2013

Aug. 09, 2014

Dec. 31, 2014

Aug. 07, 2014

Dec. 31, 2013

Dec. 31, 2014

Nov. 30, 2011

Jan. 10, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Dec. 11, 2014

Dec. 11, 2014

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2014

Nov. 19, 2014

Sep. 20, 2013

Dec. 31, 2014

Jan. 21, 2014

Jun. 30, 2013

Dec. 31, 2014

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Jun. 30, 2013

Sep. 20, 2014

Dec. 31, 2014

Sep. 19, 2014

Sep. 20, 2014

Sep. 20, 2014

Sep. 20, 2014

Sep. 20, 2014

Sep. 20, 2014

Sep. 20, 2014

Sep. 20, 2014

Dec. 31, 2014

Dec. 31, 2013

Oct. 28, 2014

Dec. 31, 2014

Oct. 14, 2014

Oct. 14, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

USD ($)

USD ($)

USD ($)

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Senior Notes

Colombian Loan

Colombian Loan

Colombian Long Term Credit Facility

Colombian Long Term Credit Facility

Costa Rica Loan

Costa Rica Loan

Costa Rica Loan

Richland Notes

Richland Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Three Point Four Zero and Five Point Zero Percent Senior Notes

Reopened Three Point Four Zero Percent Senior Notes

Commercial Mortgage Pass Through Certificates Series 2013

Commercial Mortgage Pass Through Certificates Series 2013

Commercial Mortgage Pass Through Certificates Series 2013

Commercial Mortgage Pass Through Certificates Series 2013

GTP Notes

GTP Notes

GTP Notes

GTP Notes

GTP Notes

GTP Notes

3.50% Senior Notes

3.50% Senior Notes

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2014

Credit Facility 2014

Term Loan 2013

Term Loan 2013

Term Loan 2013

Term Loan 2013

Term Loan 2013

Term Loan 2013

Term Loan 2013

Term Loan 2013

Credit Facility 2012

3.40% Senior Notes

3.40% Senior Notes

3.40% Senior Notes

5.00% Senior Notes

5.00% Senior Notes

5.00% Senior Notes

3.450% Senior Notes

3.450% Senior Notes

3.450% Senior Notes

3.450% Senior Notes

South African Facility

South African Facility

Reopened Five Point Zero Percent

Colombian Bridge Loan

Colombian Bridge Loan

Ghana Loan

Ghana Loan

Ghana Loan

2014 Ghana Loan

2014 Ghana Loan

2014 Ghana Loan

Uganda Loan

Uganda Loan

Mexican loan

Mexican loan

Mexican loan

Mexican loan

BR Towers Debt

BR Towers Debt

BR Towers Sublimit A

BR Towers Sublimit A

BR Towers Sublimit A

BR Towers Sublimit C

BR Towers Sublimit C

BR Towers Sublimit C

BR Towers Sublimit C

BR Towers Private Debentures

BR Towers Private Debentures

BR Towers Private Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Credit Facility

BR Towers Credit Facility

BR Towers Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Secured Tower Revenue Securities, Series 2013-1A

Secured Tower Revenue Securities, Series 2013-1A

Secured Tower Revenue Securities, Series 2013-2A

Secured Tower Revenue Securities, Series 2013-2A

Unsecured Debt

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Senior Notes

Senior Notes

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Senior Notes

Senior Notes

Revolving Credit Facility

Revolving Credit Facility

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Revolving Credit Facility

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Revolving Credit Facility

Senior Notes

Short-term Debt

Short-term Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Secured Debt

Secured Debt

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Unsecured Debt

Unsecured Debt

Unsecured Debt

Secured Debt

Secured Debt

Secured Debt

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Unsecured Debt

Short Term Credit Facility

Indian Facility

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2013

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

Credit Facility 2014

South African Facility

South African Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

Colombian Credit Facility

BR Towers Credit Facility

BR Towers Credit Facility

BR Towers Credit Facility

BR Towers Credit Facility

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Series 2010-1 Class C

Series 2010-2 Class C

Series 20102 Class F

Minimum

Maximum

USD ($)

USD ($)

USD ($)

USD ($)

Secured Tower Revenue Securities, Series 2013-1A

Secured Tower Revenue Securities, Series 2013-2A

USD ($)

USD ($)

USD ($)

USD ($)

Minimum

Maximum

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

renewal_periods

USD ($)

USD ($)

USD ($)

London Interbank Offered Rate (LIBOR)

Minimum

Minimum

Maximum

Maximum

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

ZAR

USD ($)

USD ($)

USD ($)

USD ($)

GHS

USD ($)

USD ($)

GHS

USD ($)

USD ($)

USD ($)

USD ($)

MXN

USD ($)

MXN

USD ($)

BRL

USD ($)

BRL

USD ($)

BRL

Minimum

USD ($)

BRL

BRL

BRL

USD ($)

USD ($)

BRL

USD ($)

BRL

BRL

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Multicurrency Borrowings

Letter of Credit

Swingline Loan

Additional Commitments

London Interbank Offered Rate (LIBOR)

Minimum

Minimum

Minimum

Maximum

Maximum

Maximum

USD ($)

USD ($)

USD ($)

London Interbank Offered Rate (LIBOR)

Minimum

Minimum

Minimum

Maximum

Maximum

Maximum

USD ($)

USD ($)

USD ($)

USD ($)

COP

USD ($)

COP

Secured Debt

Secured Debt

Unsecured Debt

Unsecured Debt

propertyinterests

towers

Series

propertyinterests

London Interbank Offered Rate (LIBOR)

Base Rate

London Interbank Offered Rate (LIBOR)

Base Rate

Loan

renewal_periods

USD ($)

USD ($)

USD ($)

USD ($)

London Interbank Offered Rate (LIBOR)

Base Rate

London Interbank Offered Rate (LIBOR)

Base Rate

London Interbank Offered Rate (LIBOR)

Base Rate

London Interbank Offered Rate (LIBOR)

Base Rate

USD ($)

USD ($)

Minimum

Maximum

subsidiary

subsidiary

site

Debt Instrument [Line Items]

Number of communications sites

5,195

2,845

Number of subsidiaries

2

2

Long-term debt

$14,608,708,000

$14,478,278,000

$500,000,000

$500,000,000

$1,300,000,000

$1,300,000,000

$0

$35,697,000

$0

$70,063,000

$0

$32,600,000

$196,500,000

$203,683,000

[1]

$205,436,000

[1]

$209,300,000

$1,800,000,000

$1,263,983,000

[2]

$1,537,881,000

[2]

$1,490,000,000

$993,230,000

$992,520,000

$1,500,000,000

[3]

$1,500,000,000

[3]

$1,500,000,000

$1,005,509,000

$749,373,000

$1,010,834,000

$499,455,000

$646,394,000

$0

$0

[4]

175,200,000

$158,327,000

[4]

$68,651,000

[4],[5]

220,900,000

$0

[4],[5]

$69,004,000

[6],[7]

$66,926,000

[6],[7]

$377,470,000

[3],[8]

$263,426,000

[3],[8]

3,900,000,000

$261,100,000

671,500,000

$7,600,000

20,200,000

$100,000

200,000

330,000,000

315,300,000

[2]

$118,688,000

[2],[9]

$0

[9]

300,000,000

$16,400,000

43,500,000

$75,133,000

[10],[3]

$88,334,000

[10],[3]

$83,596,000

[11],[3]

$0

[11],[3]

200,000,000,000

$16,389,000

[9]

$0

[9]

Series of securities, number

2

Weighted average life, years

8 years 7 months

Weighted average, interest rate

2.65%

10.34%

Cash Trap Debt Service Credit Ratio

1.3

Minimum, DSCR

1.15

1.1

Restricted cash

118,800,000

20,900,000

Short-term Debt

250,000,000

0

56,058,000

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

-3,379,000

-35,288,000

0

-1,300,000

3,000,000

1,200,000

3,200,000

Property interests under communications sites

1,517

1,035

Debt Instrument, Covenant, Threshold For Majority Of Holders In Event Of Default

50.00%

Long-term Debt, Fair Value

323,400,000

313,100,000

48,100,000

Long-term debt, stated interest rate

5.35%

6.39%

9.52%

5.35%

[12]

9.52%

[12]

1.55%

[12]

3.07%

[12]

2.36%

[12]

7.63%

[12]

3.50%

[12]

3.40%

[12]

3.40%

5.00%

[12]

5.00%

[12]

3.45%

[12]

3.45%

21.87%

21.87%

7.40%

8.36%

[12]

3.50%

[12]

10.80%

[12]

Limit on indebtedness

800,000,000

5,000,000

800,000,000

Percentage Of Gross Amounts Maximum

5.00%

30.00%

Line of Credit Facility, Remaining Borrowing Capacity

1,700,000

4,600,000

Line of Credit Facility, Unused Capacity, Commitment Fee Percentage

0.10%

0.10%

Long-term debt, face value

32,600,000

196,000,000

250,000,000

1,000,000,000

[13]

1,000,000,000

[13]

650,000,000

650,000,000

500,000,000

Line of credit facility, maximum borrowing capacity

2,000,000,000

1,000,000,000

1,200,000,000

68,700,000

5,200,000,000

1,000,000,000

10,000,000

1,500,000,000

2,000,000,000

1,500,000,000

96,800,000

200,000,000,000

Borrowings under credit facilities

2,187,000,000

3,507,000,000

2,582,000,000

374,700,000

4,900,000,000

912,000,000

1,300,000,000

Repayments of debt

80,400,000

1,100,000,000

Debt Instrument, Basis Spread on Variable Rate

1.25%

1.13%

0.13%

2.25%

1.25%

1.50%

1.50%

4.80%

0.90%

6.00%

1.25%

1.13%

0.13%

2.00%

1.00%

1.25%

1.13%

0.13%

2.00%

1.00%

4.00%

Base rate borrowing margin

3.75%

Percentage of debt hedged by interest rate swap agreements

50.00%

Derivative, Variable Interest Rate

9.05%

Number of bridge loans

6

Proceeds from the issuance of debt

3,000,000

763,800,000

1,780,000,000

641,100,000

Debt Instrument, Unamortized Premium

5,500,000

7,700,000

26,900,000

Line of credit facility, capacity available

500,000,000

1,000,000,000

200,000,000

50,000,000

750,000,000

Debt instrument, term

5 years

Annual renewal periods, number

2

Debt instrument, length of renewal period

1 year

Line of credit facility, commitment fee percentage

0.15%

0.13%

0.40%

0.15%

0.13%

0.40%

Maximum Adjusted EBITDA

3.5

0.5

0.5

Repayment of indebtedness under credit facility

88,000,000

710,000,000

2,800,000,000

263,000,000

Letters of credit, amount outstanding

3,200,000

8,000,000

Line of credit facility, amount of increase in borrowing capacity

50,000,000

Letter of credit, amount of increase in borrowing capacity

200,000,000

Number of renewal periods

2

Line of credit facility, optional additional commitments

500,000,000

Debt amount of principal redemption percentage

100.00%

Repurchase price as a percentage of principal

101.00%

Capital lease obligations

$95,400,000

$73,400,000

Capital lease obligation and notes payable, interest rates, minimum

2.27%

Capital lease obligation and notes payable, interest rate, maximum

8.00%

Capital lease obligation and notes payable, interest maturity, minimum

1 year

Capital lease obligation and notes payable, maturity, maximum

70 years

[1]

Includes approximately $7.7 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments recognized upon the acquisition of Unison Holdings, LLC and Unison Site Management II, L.L.C. (collectively, “Unison”).

[2]

Includes approximately $26.9 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments for debt assumed upon the acquisition of MIPT.

[3]

Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.

[4]

During the year ended December 31, 2014, the joint venture in Ghana converted $175.2 million of existing notes under the U.S. Dollar-denominated Ghana Loan into a new 220.9 million GHS (approximately $68.7 million) denominated shareholder loan. The remaining balance of the Ghana Loan was converted into equity of the respective holders.

[5]

Denominated in GHS. As of December 31, 2014, the aggregate principal amount outstanding under the 2014 Ghana Loan is 220.9 million GHS.

[6]

Includes approximately $2.1 million of capitalized accrued interest pursuant to the terms of the loan agreement.

[7]

Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.

[8]

Denominated in Mexican Pesos (“MXN”). As of December 31, 2014, the aggregate principal amount outstanding under the Mexican Loan is 3.9 billion MXN.

[9]

Denominated in Brazilian Real (“BRL”). As of December 31, 2014, the aggregate principal amount outstanding under the BR Towers Debentures and the BR Towers Credit Facility is 315.3 million BRL and 43.5 million BRL respectively. A portion of the debt accrues interest at a variable rate.

[10]

Denominated in South African Rand (“ZAR”). As of December 31, 2014, the aggregate principal amount outstanding under the South African Facility is 869.3 million ZAR.

[11]

Denominated in Colombian Pesos (“COP”). As of December 31, 2014, the aggregate principal amount outstanding under the Colombian Credit Facility is 200.0 billion COP.

[12]

Represents the interest rate and maturity date as of December 31, 2014 and does not reflect the impact of interest rate swap agreements.

[13]

The original issue date for the 3.40% Notes and the 5.00% Notes was August 19, 2013. The issue date for the reopened 3.40% Notes and the reopened 5.00% Notes was January 10, 2014.

LongTerm_Obligations_LongTerm_

Long-Term Obligations (Long-Term Financing Arrangements) (Details)

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Mar. 15, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Oct. 02, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Oct. 29, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Jan. 10, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Aug. 07, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Jan. 10, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Nov. 19, 2014

Nov. 19, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Oct. 28, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

USD ($)

USD ($)

Subsidiaries

Subsidiaries

Parent

Parent

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Commercial Mortgage Pass Through Certificates Series 2013

Commercial Mortgage Pass Through Certificates Series 2013

Commercial Mortgage Pass Through Certificates Series 2013

GTP Notes

GTP Notes

GTP Notes

BR Towers Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Debentures

BR Towers Credit Facility

BR Towers Credit Facility

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Secured Cellular Site Revenue Notes

Mexican loan

Mexican loan

Mexican loan

Colombian Long Term Credit Facility

Colombian Long Term Credit Facility

Colombian Bridge Loan

Colombian Bridge Loan

Colombian Loan

Colombian Loan

Costa Rica Loan

Costa Rica Loan

Shareholder Loans

Shareholder Loans

BR Towers Debt

BR Towers Debt

BR Towers Sublimit A

BR Towers Sublimit A

BR Towers Sublimit A

BR Towers Sublimit C

BR Towers Sublimit C

BR Towers Sublimit C

BR Towers Sublimit B

Ghana Loan

Ghana Loan

Ghana Loan

2014 Ghana Loan

2014 Ghana Loan

2014 Ghana Loan

Uganda Loan

Uganda Loan

Term Loan 2013

Term Loan 2013

Term Loan 2013

4.625% Senior Notes

4.625% Senior Notes

7.00% Senior Notes

7.00% Senior Notes

4.50% Senior Notes

4.50% Senior Notes

3.40% Senior Notes

3.40% Senior Notes

3.40% Senior Notes

7.25% Senior Notes

7.25% Senior Notes

5.05% Senior Notes

5.05% Senior Notes

3.450% Senior Notes

3.450% Senior Notes

3.450% Senior Notes

5.90% Senior Notes

5.90% Senior Notes

4.70% Senior Notes

4.70% Senior Notes

3.50% Senior Notes

3.50% Senior Notes

5.00% Senior Notes

5.00% Senior Notes

5.00% Senior Notes

Minimum

Minimum

Minimum

Maximum

Maximum

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

USD ($)

USD ($)

USD ($)

USD ($)

Secured Tower Revenue Securities, Series 2013-1A

Secured Tower Revenue Securities, Series 2013-1A

Secured Tower Revenue Securities, Series 2013-2A

Secured Tower Revenue Securities, Series 2013-2A

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Secured Debt

Secured Debt

Secured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Short-term Debt

Short-term Debt

Unsecured Debt

Unsecured Debt

Secured Debt

Secured Debt

Unsecured Debt

Unsecured Debt

Secured Debt

Secured Debt

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Revolving Credit Facility

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

Senior Notes

GTP Notes

Secured Cellular Site Revenue Notes

BR Towers Sublimit C

GTP Notes

Secured Cellular Site Revenue Notes

BR Towers Sublimit B

BR Towers Sublimit B

BR Towers Credit Facility

BR Towers Credit Facility

South African Facility

South African Facility

South African Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

Credit Facility 2013

Credit Facility 2013

Credit Facility 2014

Credit Facility 2014

Minimum

Maximum

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Secured Tower Revenue Securities, Series 2013-1A

Secured Tower Revenue Securities, Series 2013-2A

USD ($)

USD ($)

USD ($)

USD ($)

BRL

USD ($)

BRL

USD ($)

BRL

USD ($)

USD ($)

USD ($)

USD ($)

MXN

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

BRL

USD ($)

BRL

USD ($)

BRL

USD ($)

GHS

USD ($)

USD ($)

GHS

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Secured Debt

Secured Debt

Revolving Credit Facility

Secured Debt

Secured Debt

USD ($)

BRL

Secured Debt

Secured Debt

USD ($)

ZAR

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

BR Towers Credit Facility

BR Towers Credit Facility

USD ($)

USD ($)

Unsecured Debt

Unsecured Debt

Debt Instrument [Line Items]

Total long term obligation

$14,608,708,000

$14,478,278,000

$3,962,553,000

$4,428,792,000

$10,550,773,000

$9,976,108,000

$500,000,000

$500,000,000

$1,300,000,000

$1,300,000,000

$1,800,000,000

$1,263,983,000

[1]

$1,537,881,000

[1]

$1,490,000,000

$118,688,000

[1],[2]

315,300,000

[1]

$0

[2]

300,000,000

$16,400,000

43,500,000

$203,683,000

[3]

$205,436,000

[3]

$209,300,000

$263,426,000

[4],[5]

3,900,000,000

$377,470,000

[4],[5]

$0

$70,063,000

$0

$35,697,000

$0

$32,600,000

$137,655,000

[6]

$225,253,000

[6]

$261,100,000

671,500,000

$7,600,000

20,200,000

$100,000

200,000

$0

[7]

175,200,000

$158,327,000

[7]

$68,651,000

[7],[8]

220,900,000

$0

[7],[8]

$69,004,000

[10],[9]

$66,926,000

[10],[9]

$1,500,000,000

[4]

$1,500,000,000

[4]

$1,500,000,000

$599,958,000

[11]

$599,794,000

[11]

$500,000,000

$500,000,000

$999,631,000

$999,520,000

$1,005,509,000

$749,373,000

$297,260,000

$296,748,000

$699,496,000

$699,413,000

$646,394,000

$0

$499,474,000

$499,414,000

$698,987,000

$698,871,000

$993,230,000

$992,520,000

$1,010,834,000

$499,455,000

$10,400,000

27,600,000

$16,389,000

[2]

$0

[2]

$75,133,000

[12],[4]

$88,334,000

[12],[4]

$83,596,000

[13],[4]

$0

[13],[4]

Debt Instrument, Basis Spread on Variable Rate

1.50%

1.50%

4.80%

0.90%

6.00%

4.00%

Short-term Debt

0

56,058,000

Line of credit facility, amount outstanding

869,300,000

0

[4]

1,853,000,000

[4]

1,100,000,000

[14],[4]

88,000,000

[14],[4]

Other debt, including capital lease obligations

95,382,000

73,378,000

Debt, long-term and short-term, combined amount

14,608,708,000

Less current portion of long-term obligations

-897,624,000

-70,132,000

Long-term debt, excluding current maturities

13,711,084,000

14,408,146,000

Long-term debt, stated interest rate

1.55%

[15]

3.07%

[15]

7.40%

21.87%

21.87%

4.63%

[15]

7.00%

[15]

4.50%

[15]

3.40%

[15]

3.40%

7.25%

[15]

5.05%

[15]

3.45%

[15]

3.45%

5.90%

[15]

4.70%

[15]

3.50%

[15]

5.00%

[15]

5.00%

[15]

2.36%

[15]

5.35%

[15]

7.63%

[15]

9.52%

[15]

8.36%

[15]

3.50%

[15]

10.80%

[15]

Interest rate at period end

7.40%

[15]

7.40%

[15]

4.82%

[15]

4.82%

[15]

10.80%

[16]

5.90%

[16]

3.50%

5.84%

1.41%

[15]

9.88%

[15]

9.88%

[15]

1.41%

[15]

1.41%

[15]

Debt instrument, unamortized premium

$26,900,000

$7,700,000

[1]

Includes approximately $26.9 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments for debt assumed upon the acquisition of MIPT.

[2]

Denominated in Brazilian Real (“BRL”). As of December 31, 2014, the aggregate principal amount outstanding under the BR Towers Debentures and the BR Towers Credit Facility is 315.3 million BRL and 43.5 million BRL respectively. A portion of the debt accrues interest at a variable rate.

[3]

Includes approximately $7.7 million of the remaining portion of unamortized premium recorded as a result of fair value adjustments recognized upon the acquisition of Unison Holdings, LLC and Unison Site Management II, L.L.C. (collectively, “Unison”).

[4]

Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.

[5]

Denominated in Mexican Pesos (“MXN”). As of December 31, 2014, the aggregate principal amount outstanding under the Mexican Loan is 3.9 billion MXN.

[6]

Reflects balances owed to the Company’s joint venture partners in Ghana and Uganda. The Ghana loan is denominated in Ghanaian Cedi (“GHS”) and the Uganda loan is denominated in USD.

[7]

During the year ended December 31, 2014, the joint venture in Ghana converted $175.2 million of existing notes under the U.S. Dollar-denominated Ghana Loan into a new 220.9 million GHS (approximately $68.7 million) denominated shareholder loan. The remaining balance of the Ghana Loan was converted into equity of the respective holders.

[8]

Denominated in GHS. As of December 31, 2014, the aggregate principal amount outstanding under the 2014 Ghana Loan is 220.9 million GHS.

[9]

Includes approximately $2.1 million of capitalized accrued interest pursuant to the terms of the loan agreement.

[10]

Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.

[11]

On February 11, 2015, the Company redeemed all of the outstanding 4.625% senior notes due 2015. See note 24.

[12]

Denominated in South African Rand (“ZAR”). As of December 31, 2014, the aggregate principal amount outstanding under the South African Facility is 869.3 million ZAR.

[13]

Denominated in Colombian Pesos (“COP”). As of December 31, 2014, the aggregate principal amount outstanding under the Colombian Credit Facility is 200.0 billion COP.

[14]

On September 19, 2014, the Company amended and restated its $1.0 billion senior unsecured revolving credit facility as described below.

[15]

Represents the interest rate and maturity date as of December 31, 2014 and does not reflect the impact of interest rate swap agreements.

[16]

Sublimit A and Sublimit C accrue interest at a per annum rate equal to 4.80% plus 1.00% and 0.90%, respectively, above the Long-Term Interest Rates disclosed by the Central Bank of Brazil (the “LTIR”). If the LTIR exceeds 6.00%, the amount of interest payable on the portion of the LTIR exceeding 6.00% will be capitalized in a manner pursuant to the terms of the loan agreement.

LongTerm_Obligations_Schedule_

Long-Term Obligations (Schedule of GTP Securitizations) (Details) (Secured Debt, GTP Notes, USD $)	12 Months Ended
	Dec. 31, 2014
Series 2011-1 Class C Notes
Debt Instrument [Line Items]
Principal amount	$70,000,000
Long-term debt, stated interest rate	3.97%
Series 2011-2 Class C Notes
Debt Instrument [Line Items]
Principal amount	490,000,000
Long-term debt, stated interest rate	4.35%
Series 2011-2 Class F Notes
Debt Instrument [Line Items]
Principal amount	155,000,000
Long-term debt, stated interest rate	7.63%
Series 2012-1 Class A Notes
Debt Instrument [Line Items]
Principal amount	100,000,000	[1]
Long-term debt, stated interest rate	3.72%	[1]
Series 2012-2 Class A Notes
Debt Instrument [Line Items]
Principal amount	114,000,000	[1]
Long-term debt, stated interest rate	4.34%	[1]
Series 2012-2 Class B Notes
Debt Instrument [Line Items]
Principal amount	41,000,000
Long-term debt, stated interest rate	6.41%
Series 2012-2 Class C Notes
Debt Instrument [Line Items]
Principal amount	27,000,000
Long-term debt, stated interest rate	7.36%
Series 2013-1 Class C Notes
Debt Instrument [Line Items]
Principal amount	190,000,000
Long-term debt, stated interest rate	2.36%
Series 2013-1 Class F Notes
Debt Instrument [Line Items]
Principal amount	55,000,000
Long-term debt, stated interest rate	4.70%
MIPT
Debt Instrument [Line Items]
Repayments of long-term debt	1,400,000
MIPT Acquisition
Debt Instrument [Line Items]
Repayments of long-term debt	$3,500,000
[1]	Does not reflect MIPT’s repayment of approximately $1.4 million aggregate principal amount prior to the date of acquisition and the Company’s repayment of approximately $3.5 million aggregate principal amount after the date of acquisition in accordance with the repayment schedules.

LongTerm_Obligations_Long_Term

Long-Term Obligations Long Term Obligations (Schedule of BR Towers credit facility sublimits) (Details) (Revolving Credit Facility)	12 Months Ended
	Dec. 31, 2014
BR Towers Sublimit A
Debt Instrument [Line Items]
Interest rate at period end	10.80%	[1]
Debt Instrument, Basis Spread on Variable Rate	4.80%
Debt instrument, additional spread on variable rate	1.00%
BR Towers Sublimit B
Debt Instrument [Line Items]
Interest rate at period end	3.50%
BR Towers Sublimit C
Debt Instrument [Line Items]
Interest rate at period end	5.90%	[1]
Debt Instrument, Basis Spread on Variable Rate	0.90%
Minimum | BR Towers Sublimit C
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	6.00%
[1]	Sublimit A and Sublimit C accrue interest at a per annum rate equal to 4.80% plus 1.00% and 0.90%, respectively, above the Long-Term Interest Rates disclosed by the Central Bank of Brazil (the “LTIR”). If the LTIR exceeds 6.00%, the amount of interest payable on the portion of the LTIR exceeding 6.00% will be capitalized in a manner pursuant to the terms of the loan agreement.

LongTerm_Obligations_Long_Term1

Long-Term Obligations Long Term Obligations (Schedule of shareholder loans) (Details)

12 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

USD ($)

USD ($)

USD ($)

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

Unsecured Debt

2014 Ghana Loan

2014 Ghana Loan

2014 Ghana Loan

Uganda Loan

Uganda Loan

Ghana Loan

Ghana Loan

Ghana Loan

USD ($)

GHS

USD ($)

USD ($)

USD ($)

USD ($)

GHS

USD ($)

Debt Instrument [Line Items]

Long-term debt

$14,608,708,000

$14,478,278,000

$68,651,000

[1],[2]

220,900,000

$0

[1],[2]

$69,004,000

[3],[4]

$66,926,000

[3],[4]

$0

[1]

175,200,000

$158,327,000

[1]

Debt Instrument, Interest Rate, Stated Percentage

21.87%

21.87%

Interest rate at period end

5.84%

Line of credit facility, maximum borrowing capacity

68,700,000

Interest Costs Capitalized

$2,800,000

$1,800,000

$1,900,000

$2,100,000

[1]

During the year ended December 31, 2014, the joint venture in Ghana converted $175.2 million of existing notes under the U.S. Dollar-denominated Ghana Loan into a new 220.9 million GHS (approximately $68.7 million) denominated shareholder loan. The remaining balance of the Ghana Loan was converted into equity of the respective holders.

[2]

Denominated in GHS. As of December 31, 2014, the aggregate principal amount outstanding under the 2014 Ghana Loan is 220.9 million GHS.

[3]

Includes approximately $2.1 million of capitalized accrued interest pursuant to the terms of the loan agreement.

[4]

Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.

LongTerm_Obligations_Aggregate

Long-Term Obligations (Aggregate Carrying Value of Long-Term Debt) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
2015	$897,624
2016	758,054
2017	706,488
2018	1,793,100
2019	3,163,859
Thereafter	7,254,208
Total cash obligations	14,573,333
Unamortized discounts and premiums, net	-35,375
Balance as of December 31, 2014	$14,608,708	$14,478,278

LongTerm_Obligations_Schedule_1

Long-Term Obligations (Schedule of Debt Discounts) (Details) (Senior Notes, USD $)	Dec. 31, 2014		Aug. 07, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
4.625% Senior Notes
Debt Instrument [Line Items]
Principal amount	$600,000
Unamortized (Discount) Premium	-42			-206
7.00% Senior Notes
Debt Instrument [Line Items]
Principal amount	500,000
Unamortized (Discount) Premium	0			0
4.50% Senior Notes
Debt Instrument [Line Items]
Principal amount	1,000,000
Unamortized (Discount) Premium	-369			-480
3.40% Senior Notes
Debt Instrument [Line Items]
Principal amount	1,000,000	[1]
Unamortized (Discount) Premium	5,509	[1]		-627	[1]
7.25% Senior Notes
Debt Instrument [Line Items]
Principal amount	300,000
Unamortized (Discount) Premium	-2,740			-3,252
5.05% Senior Notes
Debt Instrument [Line Items]
Principal amount	700,000
Unamortized (Discount) Premium	-504			-587
3.450% Senior Notes
Debt Instrument [Line Items]
Principal amount	650,000		650,000
Unamortized (Discount) Premium	-3,606			0
5.90% Senior Notes
Debt Instrument [Line Items]
Principal amount	500,000
Unamortized (Discount) Premium	-526			-586
4.70% Senior Notes
Debt Instrument [Line Items]
Principal amount	700,000
Unamortized (Discount) Premium	-1,013			-1,129
3.50% Notes
Debt Instrument [Line Items]
Principal amount	1,000,000
Unamortized (Discount) Premium	-6,770			-7,480
5.00% Senior Notes
Debt Instrument [Line Items]
Principal amount	1,000,000	[1]
Unamortized (Discount) Premium	$10,834	[1]		($545)	[1]
[1]	The original issue date for the 3.40% Notes and the 5.00% Notes was August 19, 2013. The issue date for the reopened 3.40% Notes and the reopened 5.00% Notes was January 10, 2014.

Other_NonCurrent_Liabilities_O

Other Non-Current Liabilities (Other Non-Current Liabilities) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Other Liabilities, Noncurrent [Abstract]
Unearned revenue	$415,809	$278,295	[1]
Deferred rent liability	303,442	273,318	[1]
Other miscellaneous liabilities	309,131	251,655	[1]
Balance as of December 31,	$1,028,382	$803,268	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Asset_Retirement_Obligations_N

Asset Retirement Obligations (Narrative) (Details) (USD $)	Dec. 31, 2014
In Billions, unless otherwise specified
Asset Retirement Obligation [Abstract]
Estimated undiscounted future cash outlay for asset retirement obligations	$1.80

Asset_Retirement_Obligations_C

Asset Retirement Obligations (Carrying Value of Asset Retirement Obligations) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Asset Retirement Obligation [Abstract]
Asset Retirement Obligation, Foreign Currency Translation	($38,500,000)		($19,800,000)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance as of January 1,	549,548,000	[1]	435,624,000	[1]
Additions	52,623,000		117,330,000	[1]
Accretion expense	40,325,000		34,045,000	[1]
Revisions in estimates	-32,311,000	[2]	-36,492,000	[1],[2]
Settlements	-1,150,000		-959,000	[1]
Balance as of December 31,	$609,035,000		$549,548,000	[1]
[1]	December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Revisions in estimates include the impact of approximately $(38.5) million and $(19.8) million of foreign currency translation for the years ended December 31, 2014 and 2013, respectively.

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Narrative) (Details)

12 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Oct. 31, 2014

Oct. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

USD ($)

USD ($)

USD ($)

Costa Rica Loan

Colombian Credit Facility

Colombian Credit Facility

South African Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

Securitization 2007

Minimum

Maximum

Senior Notes

Designated as Hedging Instrument

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

interest_rate_swap

USD ($)

COP

interest_rate_swap

USD ($)

COP

USD ($)

South African Facility

South African Facility

7.00% Senior Notes

USD ($)

South African Facility

South African Facility

South African Facility

South African Facility

Colombian Long Term Credit Facility

USD ($)

ZAR

USD ($)

ZAR

USD ($)

Derivative [Line Items]

Reclassification of unrealized losses on cash flow hedges to net income, tax

$158,000

$237,000

$208,000

$1,000,000

Debt Instrument, Interest Rate, Stated Percentage

7.00%

[1]

Number of interest rate swap agreements

3

15

Derivative, Lower Fixed Interest Rate Range

6.09%

Derivative, Higher Fixed Interest Rate Range

7.83%

Derivative Asset, Notional Amount

41,800,000

100,000,000,000

38,080,000

440,614,000

44,732,000

469,354,000

Interest rate

5.74%

5.74%

Derivative, Loss on Derivative

1,400,000

3,000,000,000

Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net

700,000

Amortization period

5 years

Reclassification of unrealized losses on cash flow hedges to net income

$3,448,000

$2,572,000

$1,132,000

$200,000

[1]

Represents the interest rate and maturity date as of December 31, 2014 and does not reflect the impact of interest rate swap agreements.

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Schedule of Derivative Financial Instruments) (Details)

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

In Thousands, unless otherwise specified

USD ($)

South African Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

Costa Rica Loan

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

Interest Rate Swap

interest_rate_swap

USD ($)

COP

USD ($)

South African Facility

South African Facility

South African Facility

South African Facility

Colombian Long Term Credit Facility

Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

2014 Colombian Long Term Credit Facility

Costa Rica Loan

interest_rate_swap

USD ($)

ZAR

USD ($)

ZAR

USD ($)

COP

USD ($)

COP

USD ($)

Derivative [Line Items]

Number of interest rate swap agreements

15

3

Derivative Asset, Notional Amount

$41,800

100,000,000

$38,080

440,614

$44,732

469,354

Interest rate swap agreements

88

88

1,016

90

939

Derivative Liability, Notional Amount

0

[1]

52,547

101,250,000

41,798

100,000,000

42,000

[1]

Derivative liability, fair value

($647)

$0

[1]

($1,557)

-3,000,236

($647)

-1,548,688

($628)

[1]

[1]

One of the Company’s Costa Rican subsidiaries had three interest rate swap agreements, which were terminated upon repayment of the Costa Rica Loan in February 2014.

Derivative_Financial_Instrumen4

Derivative Financial Instruments (Schedule of Interest Rate Swap Agreements Impact on Other Comprehensive Income) (Details) (Interest Expense, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Interest Expense
Derivative [Line Items]
Gain(Loss) Recognized in OCI - Effective Portion	($2,082)	$1,481	($6,220)
Gain(Loss) Reclassified from AOCI into Income - Effective Portion	($3,606)	($2,809)	($1,340)

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business combination, contingent consideration arrangements, range of outcomes, value, low	$0
Business combination, contingent consideration arrangements, range of outcomes, value, high	40,400,000
Assets held and used, original carrying value	8,900,000,000	8,554,500,000
Assets held and used long lived, net realizable value	8,888,800,000	8,538,600,000
Impairment charges to write down certain assets to net realizable value	15,300,000	15,900,000	21,500,000
Debt, long-term and short-term, combined amount	14,608,708,000
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt, long-term and short-term, combined amount		14,500,000,000
Long-term debt, fair value	15,000,000,000	14,700,000,000
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	9,700,000,000	8,600,000,000
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	5,300,000,000	6,100,000,000
Operations In Panama and Portion of Engineering Business
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate sale price	17,900,000
Property, plant and equipment	8,100,000
Intangible noncurrent assets	7,800,000
Goodwill	3,600,000
Goodwill and intangible asset impairment	2,200,000
Excluding Semaan impairment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges to write down certain assets to net realizable value	$11,200,000
Customer Concentration Risk
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Customer Concentration Risk | Sales Revenue, Net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Concentration Risk, Percentage	56.00%
Customer Concentration Risk | Sales Revenue, Net | NII Holdings [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Concentration Risk, Percentage	6.00%

Fair_Value_Measurements_Assets

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $)	Dec. 31, 2014		Dec. 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	$6,302	[1]	$18,612
Interest rate swap agreements	88
Acquisition-related contingent consideration	28,524		31,890		23,711
Interest rate swap agreements	647
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	6,302	[1]
Interest rate swap agreements	88
Interest rate swap agreements	647
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Acquisition-related contingent consideration	28,524
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments			18,612	[1]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments			18,612	[1]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Acquisition-related contingent consideration			31,890
Interest Rate Swap | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements			90
Interest rate swap agreements			2,185
Interest Rate Swap | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements			90
Interest rate swap agreements			$2,185
[1]	Consists of highly liquid investments with original maturities in excess of three months.

Fair_Value_Measurements_Contin

Fair Value Measurements (Contingent Consideration) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Acquisition-related contingent consideration	$28,524		$31,890
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of January 1	31,890		23,711
Additions	6,412		13,474
Settlements	-3,889		-8,789
Change in fair value	-225		5,743
Foreign currency translation adjustment	-4,934		-2,249
Contingent consideration, other	-730	[1]	0	[1]
Balance as of December 31	28,524		31,890
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Acquisition-related contingent consideration	28,524
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of December 31	$28,524
[1]	In connection with the sale of operations in Panama, the buyer assumed the Company’s potential obligations related to additional purchase price consideration.

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Loss (Schedule Of Accumulated Other Comprehensive Loss) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification of unrealized losses on cash flow hedges to net income, tax	$158	$237	$208
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of January 1, 2014	-311,220	-183,347
Other comprehensive loss before reclassifications, net of tax	-486,289	-130,293
Amounts reclassified from accumulated other comprehensive loss, net of tax	3,288	2,420
Net current-period other comprehensive income (loss)	-483,001	-127,873
Balance as of December 31, 2014	-794,221	-311,220	-183,347
Unrealized Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of January 1, 2014	-1,869	-4,358
Other comprehensive loss before reclassifications, net of tax	-1,966	867
Amounts reclassified from accumulated other comprehensive loss, net of tax	2,490	1,622
Net current-period other comprehensive income (loss)	524	2,489
Balance as of December 31, 2014	-1,345	-1,869
Treasury Lock
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of January 1, 2014	-3,029	-3,827
Other comprehensive loss before reclassifications, net of tax	0	0
Amounts reclassified from accumulated other comprehensive loss, net of tax	798	798
Net current-period other comprehensive income (loss)	798	798
Balance as of December 31, 2014	-2,231	-3,029
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of January 1, 2014	-306,322	-175,162
Other comprehensive loss before reclassifications, net of tax	-484,323	-131,160
Amounts reclassified from accumulated other comprehensive loss, net of tax	0	0
Net current-period other comprehensive income (loss)	-484,323	-131,160
Balance as of December 31, 2014	-790,645	-306,322
Interest Rate Swap | Unrealized Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification of unrealized losses on cash flow hedges to net income, tax	100	200
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Amounts reclassified from accumulated other comprehensive loss, net of tax	($1,000)

Income_Taxes_Narrative_Details

Income Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Income Tax Contingency [Line Items]
Excess Tax Benefit from Share-based Compensation, Operating Activities	$500,000
Income tax expense, restructuring domestic TRS	2,600,000		21,500,000
Valuation allowance	141,200,000		136,000,000
Undistributed Earnings of Foreign Subsidiaries	391,000,000
Excess tax benefit from the exercise of employee stock options	300,000,000
Tax credit carryforward	2,100,000
Unrecognized tax benefits that would impact the ETR	31,900,000		31,100,000
Impact of uncertain tax positions, minimum	0
Impact of uncertain tax positions, maximum	18,200,000
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities					2,100,000
Decrease in unrecognized tax benefits, lapse of applicable statute of limitations	5,349,000	[1]	1,218,000	[1]	4,926,000	[1]
Unrecognized tax benefits, income tax penalties and interest	-3,400,000		3,400,000		-2,900,000
Unrecognized tax benefits	31,947,000		32,545,000		34,337,000		38,886,000
Unrecognized tax benefits, income tax penalties and interest accrued	24,900,000		30,900,000
Other Noncurrent Liabilities
Income Tax Contingency [Line Items]
Unrecognized tax benefits	31,900,000		32,500,000
Federal
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	939,775,000
Subsidiaries | Federal
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$647,300,000
[1]	(1) Includes $2.1 million of effective settlements for the year ended December 31, 2012.

Income_Taxes_Income_Tax_Provis

Income Taxes (Income Tax Provision from Continuing Operations) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal, current	($2,390)	($30,322)	($18,170)
State, current	-797	-13,731	-6,321
Foreign, current	-57,934	-44,973	-53,513
Federal, deferred	-4,180	-16,318	-13,094
State, deferred	-973	-5,139	-666
Foreign, deferred	3,769	50,942	-15,540
Income tax provision	($62,505)	($59,541)	($107,304)

Income_Taxes_Components_of_Inc

Income Taxes (Components of Income from Continuing Operations Before Income Taxes and Income on Equity Method Investments) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Expense (Benefit), Continuing Operations [Abstract]
United States	$857,457	$766,772	$787,960
Foreign	8,247	-225,023	-86,666
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INCOME ON EQUITY METHOD INVESTMENTS	$865,704	$541,749	$701,294

Income_Taxes_Reconciliation_Be

Income Taxes (Reconciliation Between the U.S. Statutory Rate and the Effective Rate from Continuing Operations) (Details)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Statutory tax rate	35.00%		35.00%		35.00%
Tax adjustment related to REIT	-35.00%	[1]	-35.00%	[1]	-35.00%	[1]
State taxes, net of federal benefit	1.00%		3.00%		1.00%
Foreign taxes	2.00%		-5.00%		4.00%
Foreign withholding taxes	3.00%		6.00%		4.00%
Domestic TRS restructuring	0.00%		4.00%		0.00%
Change in valuation allowance	0.00%		0.00%		8.00%
Other	1.00%		3.00%		-2.00%
Effective tax rate	7.00%		11.00%		15.00%
Dividend paid deduction, percentage	24.00%		28.00%		18.00%
[1]	Includes 24%, 28% and 18% from dividend paid deductions in 2014, 2013 and 2012, respectively.

Income_Taxes_Components_of_the

Income Taxes (Components of the Net Deferred Tax Asset and Related Valuation Allowance) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Allowances, accruals and other items not currently deductible	$20,525	$28,077	[1]
Current deferred liabilities	-2,799	-4,547	[1]
Subtotal	17,726	23,530	[1]
Valuation allowance	-3,094	-3,638	[1]
Net current deferred tax assets	14,632	19,892	[1]
Net operating loss carryforwards	242,701	197,335	[1]
Accrued asset retirement obligations	103,975	88,884	[1]
Stock-based compensation	693	4,331	[1]
Unearned revenue	18,947	46,788	[1]
Unrealized loss on foreign currency	15,952	68,951	[1]
Items not currently deductible and other	22,142	23,908	[1]
Depreciation and amortization	-132,254	-82,068	[1]
Deferred rent	-18,355	-17,814	[1]
Other	-1,805	-5,302	[1]
Subtotal	251,996	325,013	[1]
Valuation allowance	-138,147	-132,368	[1]
Net non-current deferred tax assets	$113,849	$192,645	[1]
[1]	(1) December 31, 2013 balances have been revised to reflect purchase accounting measurement period adjustments.

Income_Taxes_Net_Operating_Los

Income Taxes (Net Operating Loss Carryforwards Expire) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Federal
Operating Loss Carryforwards [Line Items]
2015 to 2019	$0
2020 to 2024	0
2025 to 2029	510,016
2030 to 2034	429,759
Indefinite Carryforward	0
Total	939,775
State
Operating Loss Carryforwards [Line Items]
2015 to 2019	82,656
2020 to 2024	290,466
2025 to 2029	444,038
2030 to 2034	217,367
Indefinite Carryforward	0
Total	1,034,527
Foreign
Operating Loss Carryforwards [Line Items]
2015 to 2019	11,896
2020 to 2024	163,078
2025 to 2029	0
2030 to 2034	0
Indefinite Carryforward	648,731
Total	$823,705

Income_Taxes_Reconciliation_of

Income Taxes (Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	$32,545		$34,337		$38,886
Additions based on tax positions related to the current year	4,187		1,427		1,037
Additions for tax positions of prior years	3,780		0		0
Reductions for tax positions of prior years	0		-320		-221
Foreign currency	-3,216		-1,681		-439
Reduction as a result of the lapse of statute of limitations and effective settlements (1)	-5,349	[1]	-1,218	[1]	-4,926	[1]
Balance at December 31	$31,947		$32,545		$34,337
[1]	(1) Includes $2.1 million of effective settlements for the year ended December 31, 2012.

StockBased_Compensation_Narrat

Stock-Based Compensation (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$80,153,000	$68,138,000	$51,983,000
Stock based compensation expenses related to modification of the vesting and exercise terms for a certain employee's equity awards		1,100,000
Capitalized stock-based compensation expense	1,600,000
Number of shares issuable under stock incentive plan	14,300,000
Accelerated recognition of stock-based compensation expense, retirement eligibility	14,800,000	7,800,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Weighted average grant date fair value (in dollars per share)	$14.86	$19.05	$17.46
Intrinsic value of stock options exercised	58,000,000	42,100,000	59,500,000
Total unrecognized compensation expense	32,100,000
Expected recognition of stock award compensation expense weighted average period in years	2 years 0 months 0 days
Employee service share-based compensation, cash received from exercise of stock options	56,600,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years 0 months 0 days
Total unrecognized compensation expense	76,300,000
Expected recognition of stock award compensation expense weighted average period in years	2 years 0 months 0 days
Total fair value of restricted stock units vested during period	58,600,000
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan employee discount	15.00%
Employee purchase shares not exceeding of gross compensation	15.00%
Employee purchase value not exceeding	$25,000
Number of shares purchased by employees under the Employee Stock Purchase Plan	81,000	78,000	88,000
Weighted average prices per share for the ESPP	$70.48	$64.74	$51.59
Employee stock purchase plan offering, expense recognition period, months	6 months
Employee stock purchase plan, fair value per share (in dollars per share)	$14.83	$13.42	$13.64
Employee stock purchase plan, shares remain reserved for future issuance	3,400,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years

StockBased_Compensation_Assump

Stock-Based Compensation (Assumptions Used to Determine the Grant Date Fair Value for Options Granted) (Details) (Employee Stock Option)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum range of risk-free interest rate	1.46%	0.75%	0.62%
Maximum range of risk-free interest rate	1.74%	1.42%	1.03%
Weighted average risk-free interest rate	1.64%	0.91%	0.92%
Expected life of option grants	4 years 6 months 0 days	4 years 4 months 28 days	4 years 4 months 24 days
Minimum range of expected volatility of underlying stock price	21.94%	24.43%	36.53%
Maximum range of expected volatility of underlying stock price	23.35%	36.09%	37.86%
Weighted average expected volatility of underlying stock price	23.08%	33.37%	37.84%
Expected annual dividend yield	1.50%	1.50%	1.50%

StockBased_Compensation_Summar

Stock-Based Compensation (Summary of the Company's Option Activity) (Details) (Employee Stock Option, USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding as of January 1, 2014	6,106,171
Granted	1,879,594
Exercised	-1,267,320
Forfeited	-176,522
Expired	-33,488
Outstanding as of December 31, 2014	6,508,435
Exercisable as of December 31, 2014	2,992,252
Vested or expected to vest as of December 31, 2014	6,506,185
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding as of January 1, 2014	$52.81
Granted	$81.32
Exercised	$44.63
Forfeited	$74.80
Expired	$33.46
Outstanding as of December 31, 2014	$62.14
Exercisable as of December 31, 2014	$46.77
Vested or expected to vest as of December 31, 2014	$62.13
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average contractual term, outstanding	6 years 9 months 7 days
Weighted average contractual term, exercisable	4 years 10 months 2 days
Weighted average contractual term, vested or expected to vest	6 years 9 months 7 days
Aggregate intrinsic value, outstanding	$238.90
Aggregate intrinsic value, exercisable	155.8
Aggregate intrinsic value, vested or expected to vest	$238.90

StockBased_Compensation_Schedu

Stock-Based Compensation (Schedule of Options Outstanding) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	6,508,435
Range of Exercise Price Per Share Minimum Range	$18.60
Range of Exercise Price Per Share Maximum Range	$93.45
Weighted Average Exercise Price Per Share	$62.14
Weighted Average Remaining Life (Years)	6 years 9 months 7 days
Options Exercisable	2,992,252
Weighted Average Exercise Price Per Share	$46.77
Range One
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	1,553,717
Range of Exercise Price Per Share Minimum Range	$18.60
Range of Exercise Price Per Share Maximum Range	$43.11
Weighted Average Exercise Price Per Share	$36.04
Weighted Average Remaining Life (Years)	3 years 6 months 15 days
Options Exercisable	1,553,717
Weighted Average Exercise Price Per Share	$36.04
Range Two
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	971,207
Range of Exercise Price Per Share Minimum Range	$44.92
Range of Exercise Price Per Share Maximum Range	$58.60
Weighted Average Exercise Price Per Share	$49.25
Weighted Average Remaining Life (Years)	5 years 2 months 12 days
Options Exercisable	744,434
Weighted Average Exercise Price Per Share	$48.63
Range Three
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	954,608
Range of Exercise Price Per Share Minimum Range	$62
Range of Exercise Price Per Share Maximum Range	$74.06
Weighted Average Exercise Price Per Share	$62.52
Weighted Average Remaining Life (Years)	7 years 2 months 27 days
Options Exercisable	397,291
Weighted Average Exercise Price Per Share	$62.30
Range Four
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	1,232,856
Range of Exercise Price Per Share Minimum Range	$76.90
Range of Exercise Price Per Share Maximum Range	$79.45
Weighted Average Exercise Price Per Share	$76.95
Weighted Average Remaining Life (Years)	8 years 2 months 12 days
Options Exercisable	256,378
Weighted Average Exercise Price Per Share	$76.92
Range Five
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	1,796,047
Range of Exercise Price Per Share Minimum Range	$81.18
Range of Exercise Price Per Share Maximum Range	$93.45
Weighted Average Exercise Price Per Share	$81.32
Weighted Average Remaining Life (Years)	9 years 2 months 12 days
Options Exercisable	40,432
Weighted Average Exercise Price Per Share	$81.18

StockBased_Compensation_Summar1

Stock-Based Compensation (Summary of the Company's Restricted Stock Unit Activity) (Details) (Restricted Stock Units (RSUs), USD $)	12 Months Ended
	Dec. 31, 2014
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding as of January 1, 2014	1,840,137
Granted	807,582
Vested	-716,905
Forfeited	-171,997
Outstanding as of December 31, 2014	1,758,817
Expected to vest, net of estimated forfeitures, as of December 31, 2014	1,685,937
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value Outstanding as of January 1, 2014	$64.75
Weighted Average Grant Date Fair Value Granted	$81.54
Weighted Average Grant Date Fair Value Vested	$59.65
Forfeitures	$72.36
Weighted Average Grant Date Fair Value Outstanding as of December 31, 2014	$73.80
Expected to vest, net of estimated forfeitures, as of December 31, 2014	$73.59

StockBased_Compensation_Schedu1

Stock-Based Compensation (Schedule of Employee Stock Purchase Plan Valuation Assumptions) (Details) (Employee Stock)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum range of risk-free interest rate	0.60%	0.07%	0.05%
Maximum range of risk-free interest rate	0.11%	0.13%	0.12%
Weighted average risk-free interest rate	0.09%	0.10%	0.08%
Expected life of option grants	0 years 6 months 0 days	0 years 6 months 0 days	0 years 6 months 0 days
Weighted average expected volatility of underlying stock price	14.14%	12.88%	33.54%
Minimum range of expected volatility of underlying stock price	11.29%	12.21%	33.16%
Maximum range of expected volatility of underlying stock price	16.59%	13.57%	33.86%
Expected annual dividends	1.50%	1.50%	1.50%

Equity_Narrative_Details

Equity (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2011	12-May-14
Dividends Paid [Line Items]
Proceeds from the issuance of preferred stock, net	$583,105,000	$0	$0
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	62,276,000	45,496,000	55,441,000
Accrued dividend RSU	3,400,000
Dividends Declared and Paid
Dividends Paid [Line Items]
Paid dividend RSU	700,000
Convertible Preferred Stock Subject to Mandatory Redemption
Dividends Paid [Line Items]
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, rate of preferred stock	5.25%
Preferred Stock, par value (in dollars per share)	$0.01	$0.01
Preferred Stock | Convertible Preferred Stock Subject to Mandatory Redemption | Minimum
Dividends Paid [Line Items]
Conversion factor, preferred stock	0.9174
Preferred Stock | Convertible Preferred Stock Subject to Mandatory Redemption | Maximum
Dividends Paid [Line Items]
Conversion factor, preferred stock	1.1468
Preferred Stock | Convertible Preferred Stock Subject to Mandatory Redemption | Series A Preferred Stock
Dividends Paid [Line Items]
Preferred stock, shares authorized					6,000,000
Preferred Stock, par value (in dollars per share)	$0.01
Proceeds from the issuance of preferred stock, net	$582,900,000
Preferred stock, liquidation preference per share	$100
Preferred Stock | Convertible Preferred Stock Subject to Mandatory Redemption | Preferred Stock
Dividends Paid [Line Items]
Preferred stock, rate of preferred stock	5.25%

Equity_Distributions_Detail

Equity (Distributions) (Detail) (USD $)	0 Months Ended	12 Months Ended
	Dec. 02, 2014	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Common Stock
Dividends Payable [Line Items]
Common Stock, Dividends, Per Share, Declared		$1.40		$1.10		$0.90
Common Stock, Dividends Per Share, Declared, Percentage of Total		100.00%		100.00%		100.00%
Ordinary Income | Common Stock
Dividends Payable [Line Items]
Common Stock, Dividends, Per Share, Declared		$1.40		$1.10		$0.90
Common Stock, Dividends Per Share, Declared, Percentage of Total		100.00%		100.00%		100.00%
Capital Gain | Common Stock
Dividends Payable [Line Items]
Common Stock, Dividends, Per Share, Declared		$0		$0		$0
Common Stock, Dividends Per Share, Declared, Percentage of Total		0.00%		0.00%		0.00%
Return of Capital | Common Stock
Dividends Payable [Line Items]
Common Stock, Dividends, Per Share, Declared		$0		$0		$0
Common Stock, Dividends Per Share, Declared, Percentage of Total		0.00%		0.00%		0.00%
Convertible Preferred Stock Subject to Mandatory Redemption | Preferred Stock
Dividends Payable [Line Items]
Preferred stock, dividends per share, declared	$1.31	$2.67	[1]	$0	[2]	$0	[2]
Preferred Stock, Dividends Per Share, Declared, Percentage of Total		100.00%		0.00%	[2]	0.00%	[2]
Convertible Preferred Stock Subject to Mandatory Redemption | Ordinary Income | Preferred Stock
Dividends Payable [Line Items]
Preferred stock, dividends per share, declared		$2.67		$0	[2]	$0	[2]
Preferred Stock, Dividends Per Share, Declared, Percentage of Total		100.00%		0.00%	[2]	0.00%	[2]
Convertible Preferred Stock Subject to Mandatory Redemption | Capital Gain | Preferred Stock
Dividends Payable [Line Items]
Preferred stock, dividends per share, declared		$0		$0	[2]	$0	[2]
Preferred Stock, Dividends Per Share, Declared, Percentage of Total		0.00%		0.00%	[2]	0.00%	[2]
Convertible Preferred Stock Subject to Mandatory Redemption | Return of Capital | Preferred Stock
Dividends Payable [Line Items]
Preferred stock, dividends per share, declared		$0		$0	[2]	$0	[2]
Preferred Stock, Dividends Per Share, Declared, Percentage of Total		0.00%		0.00%	[2]	0.00%	[2]
[1]	In addition to the dividends disclosed above, on December 2, 2014, the Company declared a dividend of $1.3125 per share, payable on February 16, 2015 to preferred stockholders of record at the close of business on February 1, 2015.
[2]	The Company had no preferred stock outstanding during the years ended December 31, 2013 and 2012.

Impairments_Net_Loss_on_Sale_o1

Impairments, Net Loss on Sale of Long-Lived Assets (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment Impairment or Disposal [Abstract]
Impairment charges and net losses on sales or disposals of long-lived assets	$28.50	$32.50	$34.40
Impairment charges	15.3	15.9	21.5
Impairment charge, termination of tenant lease			10.8
Losses associated with the sale or disposal of certain non-core towers, other assets and other miscellaneous items	$13.20	$16.60	$12.90

Earnings_Per_Common_Share_Sche

Earnings Per Common Share (Schedule of Earnings Per Basic And Diluted by Common Class) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share [Abstract]
Net income attributable to American Tower Corporation common stockholders	$180,387	$207,593	$234,431	$202,499	$99,982	$180,123	$99,821	$171,407	$824,910	$551,333	$637,283
Dividends declared on preferred stock									-23,888	0	0
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION STOCKHOLDERS	$168,574	$199,893	$230,056	$202,499	$99,982	$180,123	$99,821	$171,407	$801,022	$551,333	$637,283
Basic weighted average common shares outstanding									395,958	395,040	394,772
Dilutive securities									4,128	4,106	4,515
Diluted weighted average common shares outstanding									400,086	399,146	399,287
Basic net income attributable to American Tower Corporation common stockholders (in dollars per share)	$0.43	$0.50	$0.58	$0.51	$0.25	$0.46	$0.25	$0.43	$2.02	$1.40	$1.61
Diluted net income attributable to American Tower Corporation common stockholders (in dollars per share)	$0.42	$0.50	$0.58	$0.51	$0.25	$0.45	$0.25	$0.43	$2	$1.38	$1.60

Earnings_Per_Common_Share_Sche1

Earnings Per Common Share (Schedule of Shares Excluded From Computation of Earnings Per Share) (Details)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issuable upon conversion of the stock-based awards and convertible notes	5		0		2
Equity Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issuable upon conversion of the stock-based awards and convertible notes	1,290		1,161		981
Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issuable upon conversion of the stock-based awards and convertible notes	4,303	[1]	0	[1]	0	[1]
[1]	Issued on May 12, 2014.

Recovered_Sheet2

Commitments And Contingencies (Narrative) (Details)

0 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

Jan. 24, 2014

Jan. 21, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2000

Dec. 31, 2014

Mar. 31, 2002

Dec. 31, 2014

USD ($)

INR

USD ($)

USD ($)

USD ($)

Television And Radio Broadcast

At T Transaction

At T Transaction

ALLTEL Transaction

ALLTEL Transaction

ALLTEL Transaction

First portfolio

USD ($)

USD ($)

USD ($)

USD ($)

sites

At T Transaction

sites

towers

USD ($)

term

sites

Loss Contingencies [Line Items]

Lessor Leasing Arrangements, Operating Leases, Term of Contract

10 years

Aggregate rent expense

$655,000,000

$495,200,000

$419,000,000

Leased assets, number of units

2,400

2,400

1,800

Average lease term (in years)

27 years

27 years

15 years

Purchased subleased towers, number of units

27

31

Aggregate purchase option price for towers

644,900,000

644,900,000

73,200,000

8,800,000

Purchase price accretion rate (per year)

10.00%

10.00%

3.00%

Successive terms to renew lease

4

4

Renewal term

5 years

5 years

Cash purchase price per tower

27,500

Purchase price of tower in shares of common stock

769

Value of potential shares payable

134,700,000

India tax assessment

$369,000,000

22,600,000,000

Commitments_and_Contingencies_1

Commitments and Contingencies (Future Minimum Rental Payments Under Non-Cancelable Operating Leases) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$574,438
2016	553,864
2017	538,405
2018	519,034
2019	502,847
Thereafter	4,214,600
Total	$6,903,188

Commitments_and_Contingencies_2

Commitments and Contingencies (Future Minimum Payments Under Capital Leases) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$15,589
2016	14,049
2017	12,905
2018	12,456
2019	10,760
Thereafter	173,313
Total minimum lease payments	239,072
Less amounts representing interest	-143,690
Present value of capital lease obligations	$95,382

Commitments_and_Contingencies_3

Commitments and Contingencies (Future Minimum Rental Receipts Under Operating Lease Agreements) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$3,438,474
2016	3,358,098
2017	3,304,255
2018	3,168,551
2019	2,916,750
Thereafter	10,495,554
Total	$26,681,682

Supplemental_Cash_Flow_Informa2

Supplemental Cash Flow Information (Supplemental Cash Flow Information and Non-Cash Investing and Financing Activities) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental Cash Flow Information [Abstract]
Cash paid for interest	$548,089	$397,366	$366,458
Cash paid for income taxes (net of refunds of $8,476, $19,701 and $20,847, respectively)	69,212	51,676	69,277
Capital Expenditures Incurred but Not yet Paid	1,121	9,147	-10,244
Purchases of property and equipment under capital leases	36,486	27,416	19,219
Fair value of debt assumed through acquisitions	463,135	1,576,186	0
Settlement of accounts receivable related to acquisitions	31,849	0	0
Conversion of third-party debt to equity	111,181	0	0
Proceeds from Income Tax Refunds	$8,476	$19,701	$20,847

Business_Segments_Narrative_De

Business Segments (Narrative) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Number of reportable segments	3
Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%

Business_Segments_Summarized_F

Business Segments (Summarized Financial Information Concerning the Company's Reportable Segments) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting Information [Line Items]
Segment revenues	$1,046,314	$1,038,188	$1,031,457	$984,089	$941,969	$807,880	$808,830	$802,728	$4,100,048		$3,361,407		$2,875,960
Segment operating expenses									1,092,428	[1]	858,329	[2]	720,718	[3]
Segment gross margin									3,018,167		2,525,313		2,169,500
Segment selling, general, administrative and development expense									271,391	[1]	236,584	[2]	187,986	[3]
Segment operating profit									2,746,776		2,288,729		1,981,514
Stock-based compensation expense									80,153		68,138		51,983
Other selling, general, administrative and development expense									96,835		112,367		89,093
Depreciation, amortization and accretion									1,003,802		800,145		644,276
Other expense (principally interest expense and other expense)									700,282		766,330		494,868
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INCOME ON EQUITY METHOD INVESTMENTS									865,704		541,749		701,294
Capital expenditures									974,404		724,532		568,048
Domestic
Segment Reporting Information [Line Items]
Segment revenues									2,732,984		2,263,682		2,013,159
Total international
Segment Reporting Information [Line Items]
Segment revenues									1,367,064		1,097,725		862,801
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Stock-based compensation expense									80,153		68,138		51,983
Other selling, general, administrative and development expense									96,835		112,367		89,093
Depreciation, amortization and accretion									1,003,802		800,145		644,276
Other expense (principally interest expense and other expense)									700,282		766,330		494,868
Capital expenditures									24,146		30,383		20,047
Operating Expense
Segment Reporting Information [Line Items]
Stock-based compensation expense									1,800		1,500		1,800
Operating Segments | Rental And Management
Segment Reporting Information [Line Items]
Segment revenues									4,006,854		3,287,090		2,803,490
Segment operating expenses									1,054,780	[1]	827,765	[2]	685,888	[3]
Segment gross margin									2,962,621		2,481,560		2,131,860
Segment selling, general, administrative and development expense									258,922	[1]	227,327	[2]	181,242	[3]
Segment operating profit									2,703,699		2,254,233		1,950,618
Capital expenditures									950,258		694,149		548,001
Operating Segments | Rental And Management | Domestic
Segment Reporting Information [Line Items]
Segment revenues									2,639,790		2,189,365		1,940,689
Segment operating expenses									515,742	[1]	405,419	[2]	357,555	[3]
Segment gross margin									2,124,048		1,783,946		1,583,134
Segment selling, general, administrative and development expense									124,944	[1]	103,989	[2]	85,663	[3]
Segment operating profit									1,999,104		1,679,957		1,497,471
Capital expenditures									576,153		416,239		268,997
Operating Segments | Rental And Management | Total international
Segment Reporting Information [Line Items]
Segment revenues									1,367,064		1,097,725		862,801
Segment operating expenses									539,038	[1]	422,346	[2]	328,333	[3]
Segment gross margin									838,573		697,614		548,726
Segment selling, general, administrative and development expense									133,978	[1]	123,338	[2]	95,579	[3]
Segment operating profit									704,595		574,276		453,147
Capital expenditures									374,105		277,910		279,004
Operating Segments | Network Development Services
Segment Reporting Information [Line Items]
Segment revenues									93,194		74,317		72,470
Segment operating expenses									37,648	[1]	30,564	[2]	34,830	[3]
Segment gross margin									55,546		43,753		37,640
Segment selling, general, administrative and development expense									12,469	[1]	9,257	[2]	6,744	[3]
Segment operating profit									43,077		34,496		30,896
Capital expenditures									0		0		0
Selling General Administrative And Development Expense
Segment Reporting Information [Line Items]
Stock-based compensation expense									78,316		66,594		50,222
TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively									10,547		22,235		14,258
TV Azteca | Operating Segments | Rental And Management
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively									10,547		22,235		14,258
TV Azteca | Operating Segments | Rental And Management | Domestic
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively									0		0		0
TV Azteca | Operating Segments | Rental And Management | Total international
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively									10,547		22,235		14,258
TV Azteca | Operating Segments | Network Development Services
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net of interest expense of $1,482, $1,483 and $1,485, respectively									$0		$0		$0
[1]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.8 million and $78.3 million, respectively.
[2]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.5 million and $66.6 million, respectively.
[3]	Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.8 million and $50.2 million, respectively.

Business_Segments_Additional_I

Business Segments (Additional Information Relating to the Company's Operating Segments) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$21,331,545		$20,283,665	[1]	$14,089,429
Corporate, Non-Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	149,273	[2]	179,483	[1],[2]	363,317	[2]
Operating Segments | Rental And Management | Domestic
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	14,348,892		13,628,137	[1]	8,471,169
Operating Segments | Rental And Management | Total international
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	6,776,013	[3]	6,428,438	[1],[3]	5,190,987	[3]
Operating Segments | Network Development Services
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$57,367		$47,607	[1]	$63,956
[1]	Balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Balances include corporate assets such as cash and cash equivalents, certain tangible and intangible assets and income tax accounts which have not been allocated to specific segments.
[3]	Balances are translated at the applicable period end exchange rate and therefore may impact comparability between periods.

Business_Segments_Summarized_G

Business Segments (Summarized Geographic Information Related to the Company's Operating Revenues) (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

$1,046,314

$1,038,188

$1,031,457

$984,089

$941,969

$807,880

$808,830

$802,728

$4,100,048

$3,361,407

$2,875,960

United States

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

2,732,984

2,263,682

2,013,159

Brazil

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

331,089

[1]

212,201

[1]

198,068

[1]

Chile

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

31,756

[1]

28,978

[1]

22,114

[1]

Colombia

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

89,421

[1]

70,901

[1]

48,424

[1]

Costa Rica

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

16,742

[1]

4,055

[1]

0

[1]

Germany

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

64,946

[1]

62,756

[1]

4,030

[1]

Ghana

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

95,486

[1]

92,114

[1]

81,818

[1]

India

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

219,566

[1]

191,355

[1]

181,863

[1]

Mexico

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

354,116

[1]

288,306

[1]

217,473

[1]

Panama (2)

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

1,243

[1],[2]

424

[1],[2]

0

[1],[2]

Peru

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

8,078

[1]

5,824

[1]

5,310

[1]

South Africa

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

98,334

[1]

91,906

[1]

80,202

[1]

Uganda

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

56,287

[1]

48,905

[1]

23,499

[1]

Total international

Segment Reporting, Other Significant Reconciling Item [Line Items]

Segment revenues

$1,367,064

$1,097,725

$862,801

[1]

Balances are translated at the applicable exchange rate and therefore may impact comparability between periods.

[2]

In September 2014, the Company completed the sale of the operations in Panama.

Business_Segments_Summarized_G1

Business Segments (Summarized Geographic Information Related to the Company's Long-lived Assets) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	$18,533,230		$17,602,649	[1]
United States
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	12,843,271	[2]	12,345,357	[1],[2]
Brazil
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	2,162,698	[3]	1,286,490	[1],[3]
Chile
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	147,413	[3]	167,318	[1],[3]
Colombia
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	320,355	[3]	390,197	[1],[3]
Costa Rica
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	127,436	[3]	129,229	[1],[3]
Germany
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	456,698	[3]	535,883	[1],[3]
Ghana
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	235,523	[3]	304,603	[1],[3]
India
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	616,266	[3]	610,744	[1],[3]
Mexico
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	1,189,854	[3]	1,348,987	[1],[3]
Panama (2)
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	0	[3],[4]	17,177	[1],[3],[4]
Peru
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	61,490	[3]	58,220	[1],[3]
South Africa
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	186,270	[3]	213,316	[1],[3]
Uganda
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	185,956	[3]	195,128	[1],[3]
Total international
Segment Reporting, Other Significant Reconciling Item [Line Items]
Long-Lived Assets	$5,689,959	[3]	$5,257,292	[1]
[1]	Balances have been revised to reflect purchase accounting measurement period adjustments.
[2]	Includes Property and equipment, net, Goodwill and Other intangible assets, net.
[3]	Balances are translated at the applicable period end exchange rate and therefore may impact comparability between periods.
[4]	In September 2014, the Company completed the sale of the operations in Panama.

Business_Segments_Major_Custom

Business Segments (Major Customers) (Details) (Customer Concentration Risk)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Sales Revenue, Net
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	56.00%
Sales Revenue, Net | AT&T Mobility
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	20.00%	18.00%	18.00%
Sales Revenue, Net | Sprint Nextel
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	15.00%	16.00%	14.00%
Sales Revenue, Net | Verizon Wireless
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	11.00%	11.00%	11.00%
Sales Revenue, Net | T-Mobile
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	10.00%	11.00%	8.00%

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data (Schedule Of Quarterly Financial Information) (Details) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Selected Quarterly Financial Information [Abstract]
Operating revenues	$1,046,314		$1,038,188		$1,031,457		$984,089		$941,969		$807,880		$808,830		$802,728		$4,100,048		$3,361,407		$2,875,960
Cost of operations	277,019	[1]	284,202	[1]	272,275	[1]	260,769	[1]	251,569	[1]	200,829	[1]	205,709	[1]	201,766	[1]	1,094,265	[1]	859,873	[1]
Operating income	345,979		384,807		402,499		353,637		292,928		308,879		312,812		299,686		1,486,922		1,214,305		1,119,719
Net income	181,597		206,630		221,659		193,313		73,925		163,222		84,113		160,948		803,199		482,208		594,025
Net income attributable to American Tower Corporation common stockholders	180,387		207,593		234,431		202,499		99,982		180,123		99,821		171,407		824,910		551,333		637,283
Dividends declared on preferred stock	-11,813		-7,700		-4,375		0		0		0		0		0		-23,888		0		0
Net income attributable to American Tower Corporation common stockholders	$168,574		$199,893		$230,056		$202,499		$99,982		$180,123		$99,821		$171,407		$801,022		$551,333		$637,283
Basic net income per common share (in dollars per share)	$0.43		$0.50		$0.58		$0.51		$0.25		$0.46		$0.25		$0.43		$2.02		$1.40		$1.61
Diluted net income per common share (in dollars per share)	$0.42		$0.50		$0.58		$0.51		$0.25		$0.45		$0.25		$0.43		$2		$1.38		$1.60
[1]	Represents Operating expenses, exclusive of Depreciation, amortization and accretion, Selling, general, administrative and development expense, and Other operating expense.

Subsequent_Events_Narrative_De

Subsequent Events Narrative (Details) (USD $)

12 Months Ended

0 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Feb. 12, 2015

Feb. 06, 2015

Feb. 11, 2015

Feb. 23, 2015

Feb. 20, 2015

Oct. 29, 2013

Jul. 21, 2014

Feb. 05, 2015

Subsequent Event [Line Items]

Cash paid for interest

$548,089,000

$397,366,000

$366,458,000

Long-term debt

14,608,708,000

14,478,278,000

Senior Notes

Subsequent Event [Line Items]

Debt amount of principal redemption percentage

100.00%

4.625% Senior Notes | Senior Notes

Subsequent Event [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

4.63%

[1]

Long-term debt

599,958,000

[2]

599,794,000

[2]

4.625% Senior Notes | Senior Notes | Subsequent Event

Subsequent Event [Line Items]

Debt amount of principal redemption percentage

100.59%

Repayments of Senior Debt

613,600,000

Cash paid for interest

10,000,000

Credit Facility 2014 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Maximum revolving loan commitments

2,500,000,000

Line of credit facility, optional additional commitments

500,000,000

Line of credit facility, maximum borrowing capacity

2,000,000,000

Term Loan 2013 | Unsecured Debt

Subsequent Event [Line Items]

Long-term debt

1,500,000,000

[3]

1,500,000,000

[3]

1,500,000,000

Term Loan 2013 | Unsecured Debt | Subsequent Event

Subsequent Event [Line Items]

Maximum incremental term loan commitment

1,000,000,000

Term Loan, optional additional commitments

500,000,000

Long-term debt

2,000,000,000

Credit Facility 2013 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Maximum revolving loan commitments

3,500,000,000

Line of credit facility, optional additional commitments

750,000,000

Line of credit facility, maximum borrowing capacity

2,750,000,000

Credit Facility 2013 | Unsecured Debt

Subsequent Event [Line Items]

Line of credit facility, maximum borrowing capacity

2,000,000,000

Proposed Verizon Transaction | Subsequent Event

Subsequent Event [Line Items]

Business Combination, Consideration Transferred

5,056,000,000

Right to lease, weighted average term

28 years

Termination fee

354,000,000

Customer Lease Initial Term Minimum

10 years

Future monthly sublease rent per tower

1,900

Fixed annual rent escalation percentage

2.00%

Bridge Loan

3,300,000,000

5,050,000,000

Line of credit facility, amount of increase in borrowing capacity

$1,750,000,000

First portfolio | Proposed Verizon Transaction | Subsequent Event

Subsequent Event [Line Items]

Number Of Sites Acquired

11,324

Second portfolio | Proposed Verizon Transaction | Subsequent Event

Subsequent Event [Line Items]

Number Of Sites Acquired

165

First measurement period | Credit Facility 2014 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

6

First measurement period | Term Loan 2013 | Unsecured Debt | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

6

First measurement period | Credit Facility 2013 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

6

Second measurement period | Credit Facility 2014 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

7.25

Second measurement period | Term Loan 2013 | Unsecured Debt | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

7.25

Second measurement period | Credit Facility 2013 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

7.25

Third measurement period | Credit Facility 2014 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

7

Third measurement period | Term Loan 2013 | Unsecured Debt | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

7

Third measurement period | Credit Facility 2013 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

7

Fourth measurement period | Credit Facility 2014 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

6

Fourth measurement period | Term Loan 2013 | Unsecured Debt | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

6

Fourth measurement period | Credit Facility 2013 | Revolving Credit Facility | Subsequent Event

Subsequent Event [Line Items]

Ratio of total debt to EBITDA

6

[1]

Represents the interest rate and maturity date as of December 31, 2014 and does not reflect the impact of interest rate swap agreements.

[2]

On February 11, 2015, the Company redeemed all of the outstanding 4.625% senior notes due 2015. See note 24.

[3]

Interest rate as of December 31, 2014. Debt accrues interest at a variable rate.

Recovered_Sheet3

Schedule III - Real Estate And Accumulated Depreciation (Schedule Of Real Estate And Accumulated Depreciation) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	site
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
SEC Schedule III, Real Estate, Number of Units	75,164	[1]
Amount of Encumbrances	$3,510,481	[2]
Real Estate And Accumulated Depreciation Carrying Amount	10,469,207	[3]
Accumulated Depreciation	($3,613,078)		($3,297,033)	($2,968,230)	($2,646,927)
Date of construction	Various
Date Acquired	Various
Percentage Of Gross Amounts Maximum	5.00%
SEC Schedule III, Real Estate and Accumulated Depreciation, Life Used for Depreciation	20 years	[3]
[1]	No single site exceeds 5% of the aggregate gross amounts at which the assets were carried at the close of the period set forth in the table above.
[2]	Certain assets secure debt of approximately $3.5 billion.
[3]	Does not include those sites under construction.

Schedule_III_Real_Estate_And_A1

Schedule III - Real Estate And Accumulated Depreciation (Activity Of Real Estate And Accumulated Depreciation) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Adjusted Real Estate Accumulated Depreciation			($3,297,033)		($2,968,230)
Adjusted Real Estate Gross At Carrying Value			9,921,276		8,290,313
SEC Schedule III, Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Gross amount at beginning	10,003,617		8,316,547		7,192,641
Acquisitions through foreclosures	0		0		0
Other acquisitions	397,837	[1]	1,415,171	[1]	739,144	[1]
Discretionary capital projects	437,720	[2]	314,126	[2]	217,935	[2]
Discretionary ground lease purchases	159,637	[3]	102,991	[3]	93,990	[3]
Redevelopment capital expenditures	96,782	[4]	89,960	[4]	67,309	[4]
Capital improvements	41,967	[5]	58,960	[5]	70,453	[5]
Start-up capital expenditures	21,173	[6]	15,757	[6]	0	[6]
Other additions	22,069	[7]	8,764	[7]	30,813	[7]
Total additions	1,177,185		2,005,729		1,219,644
Cost of real estate sold or disposed	-60,147		-48,467		-15,288
Other deductions	-569,107	[8]	-243,958	[8]	-80,450	[8]
Total deductions	-629,254		-292,425		-95,738
Balance at end	10,469,207		10,003,617		8,316,547
SEC Schedule III, Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Gross amount of accumulated depreciation at beginning	-3,297,033		-2,968,230		-2,646,927
Depreciation	-457,135		-408,693		-344,778
Other additions	-761		-264		-253
Total additions	-457,896		-408,957		-345,031
Amount of accumulated depreciation for assets sold or disposed	20,953		17,462		10,920
Other deductions	120,898	[8]	62,692	[8]	12,808	[8]
Total deductions	141,851		80,154		23,728
Balance at end	($3,613,078)		($3,297,033)		($2,968,230)
[1]	Includes acquisitions of sites.
[2]	Includes amounts incurred primarily for the construction of new sites.
[3]	Includes amounts incurred to purchase or otherwise secure the land under communications sites.
[4]	Includes amounts incurred to increase the capacity of existing sites, which results in new incremental tenant revenue.
[5]	Includes amounts incurred to maintain existing sites.
[6]	Includes amounts incurred for acquisitions and new market launches and costs that are contemplated in the business cases for these investments.
[7]	Primarily includes regional improvements and other additions.
[8]	Primarily includes foreign currency exchange rate fluctuations.