American Tower (AMT) 10-Q 27 Oct 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2016	Oct. 20, 2016
Document And Entity Information [Abstract]
Entity Registrant Name	AMERICAN TOWER CORP /MA/
Entity Central Index Key	1,053,507
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		425,687,843

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
CURRENT ASSETS:
Cash and cash equivalents	$ 530,358	$ 320,686
Restricted cash	150,655	142,193
Accounts receivable, net	273,907	227,354
Prepaid and other current assets	415,836	306,235
Total current assets	1,370,756	996,468
PROPERTY AND EQUIPMENT, net	10,452,038	9,866,424
GOODWILL	4,997,224	4,091,805
OTHER INTANGIBLE ASSETS, net	11,557,964	9,837,876
DEFERRED TAX ASSET	197,914	212,041
DEFERRED RENT ASSET	1,265,700	1,166,755
NOTES RECEIVABLE AND OTHER NON-CURRENT ASSETS	813,931	732,903
TOTAL	30,655,527	26,904,272
CURRENT LIABILITIES:
Accounts payable	105,551	96,714
Accrued expenses	571,989	516,413
Distributions payable	236,608	210,027
Accrued interest	108,077	115,672
Current portion of long-term obligations	242,992	50,202
Unearned revenue	254,336	211,001
Total current liabilities	1,519,553	1,200,029
NONCURRENT LIABILITIES
LONG-TERM OBLIGATIONS	18,436,144	17,068,807
ASSET RETIREMENT OBLIGATIONS	965,087	856,936
DEFERRED TAX LIABILITY	792,139	106,333
OTHER NON-CURRENT LIABILITIES	1,068,121	959,349
Total liabilities	22,781,044	20,191,454
COMMITMENTS AND CONTINGENCIES
REDEEMABLE NONCONTROLLING INTERESTS	1,100,202	0
EQUITY:
Common stock: $.01 par value; 1,000,000,000 shares authorized; 428,431,558 and 426,695,279 shares issued; and 425,621,532 and 423,885,253 shares outstanding, respectively	4,284	4,267
Additional paid-in capital	9,817,815	9,690,609
Distributions in excess of earnings	(1,030,663)	(998,535)
Accumulated other comprehensive loss	(1,876,374)	(1,836,996)
Treasury stock (2,810,026 shares at cost)	(207,740)	(207,740)
Total American Tower Corporation equity	6,707,396	6,651,679
Noncontrolling interests	66,885	61,139
Total equity	6,774,281	6,712,818
TOTAL	30,655,527	26,904,272
Preferred stock | Convertible Preferred Stock Subject to Mandatory Redemption | Series A Preferred Stock
EQUITY:
Preferred stock: $.01 par value: 20,000,000 authorized: 5.25%, Series A, 6,000,000 shares issued and outstanding; aggregate liquidation value of $600,000 - 5.50% Series B, 1,375,000 shares issued and outstanding, respectively; aggregate liquidation value of $1,375,000	60	60
Total equity	60	60
Preferred stock | Convertible Preferred Stock Subject to Mandatory Redemption | Series B Preferred Stock
EQUITY:
Preferred stock: $.01 par value: 20,000,000 authorized: 5.25%, Series A, 6,000,000 shares issued and outstanding; aggregate liquidation value of $600,000 - 5.50% Series B, 1,375,000 shares issued and outstanding, respectively; aggregate liquidation value of $1,375,000	14	14
Total equity	$ 14	$ 14

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
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	428,431,558	426,695,279
Common stock, shares outstanding	425,621,532	423,885,253
Treasury stock, shares	2,810,026	2,810,026
Preferred stock | 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 | Convertible Preferred Stock Subject to Mandatory Redemption | Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, dividend rate percentage (in percent)	5.25%	5.25%
Preferred stock, shares issued	6,000,000	6,000,000
Preferred stock, shares outstanding	6,000,000	6,000,000
Preferred stock, aggregate liquidation value (in dollars)	$ 600,000	$ 600,000
Preferred stock | Convertible Preferred Stock Subject to Mandatory Redemption | Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, dividend rate percentage (in percent)	5.50%	5.50%
Preferred stock, shares issued	1,375,000	1,375,000
Preferred stock, shares outstanding	1,375,000	1,375,000
Preferred stock, aggregate liquidation value (in dollars)	$ 1,375,000	$ 1,375,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
REVENUES:
Property	$ 1,497,936	$ 1,212,849	$ 4,191,779	$ 3,429,264
Services	16,909	25,061	54,340	62,211
Total operating revenues	1,514,845	1,237,910	4,246,119	3,491,475
OPERATING EXPENSES:
Property (including stock-based compensation expense of $426, $396, $1,325 and $1,218, respectively)	485,525	356,082	1,280,386	929,624
Services (including stock-based compensation expense of $172, $99, $578 and $336, respectively)	5,712	9,307	22,007	22,863
Depreciation, amortization and accretion	397,999	341,096	1,137,398	932,972
Selling, general, administrative and development expense (including stock-based compensation expense of $19,628, $17,850, $68,309 and $70,697, respectively)	131,537	114,832	405,086	354,460
Other operating expenses	14,998	15,668	37,509	40,891
Total operating expenses	1,035,771	836,985	2,882,386	2,280,810
OPERATING INCOME	479,074	400,925	1,363,733	1,210,665
OTHER INCOME (EXPENSE):
Gain (loss) on retirement of long-term obligations	0	0	830	(78,793)
Other expense (including unrealized foreign currency losses of $8,321, $77,864, $3,544 and $107,871, respectively)	(12,260)	(66,659)	(25,894)	(123,291)
Total other expense	(193,302)	(208,950)	(531,556)	(628,190)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	285,772	191,975	832,177	582,475
Income tax provision	(22,037)	(94,235)	(94,671)	(132,063)
NET INCOME	263,735	97,740	737,506	450,412
Net loss (income) attributable to noncontrolling interests	774	5,259	(10,288)	1,960
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION STOCKHOLDERS	264,509	102,999	727,218	452,372
Dividends on preferred stock	(26,781)	(26,781)	(80,344)	(63,382)
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION COMMON STOCKHOLDERS	$ 237,728	$ 76,218	$ 646,874	$ 388,990
NET INCOME PER COMMON SHARE AMOUNTS:
Basic net income attributable to American Tower Corporation common stockholders (in dollars per share)	$ 0.56	$ 0.18	$ 1.52	$ 0.93
Diluted net income attributable to American Tower Corporation common stockholders (in dollars per share)	$ 0.55	$ 0.18	$ 1.51	$ 0.92
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
BASIC (in shares)	425,517	423,375	424,831	417,280
DILUTED (in shares)	429,925	427,227	429,019	421,352
DISTRIBUTIONS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.55	$ 0.46	$ 1.59	$ 1.32
TV Azteca
OTHER INCOME (EXPENSE):
Interest income, TV Azteca, net of interest expense of $279, $40, $846 and $780, respectively	$ 2,742	$ 2,993	$ 8,206	$ 8,251
Interest expense	(279)	(40)	(846)	(780)
Excluding TV Azteca
OTHER INCOME (EXPENSE):
Interest income	6,376	4,503	16,378	11,871
Interest expense	$ (190,160)	$ (149,787)	$ (531,076)	$ (446,228)

CONSOLIDATED STATEMENTS OF OPE5

CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Stock-based compensation expense	$ 20,226	$ 18,345	$ 70,212	$ 72,251
TV Azteca
Interest expense	279	40	846	780
Property
Stock-based compensation expense	426	396	1,325	1,218
Services
Stock-based compensation expense	172	99	578	336
Selling General Administrative And Development Expense
Stock-based compensation expense	19,628	17,850	68,309	70,697
Other Expense
Unrealized foreign currency (losses) gains	$ (8,321)	$ (77,864)	$ (3,544)	$ (107,871)

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 263,735	$ 97,740	$ 737,506	$ 450,412
Other comprehensive (loss) income:
Changes in fair value of cash flow hedges, net of tax benefit of $0, $9, $0 and $18, respectively	(432)	710	(367)	365
Reclassification of unrealized (gains) losses on cash flow hedges to net income, net of tax benefit of $0, $20, $0 and $66, respectively	(108)	158	(173)	2,771
Foreign currency translation adjustments, net of tax (benefit) expense of ($1,495), ($12,863), $5,388 and ($25,275), respectively	(91,608)	(600,798)	(43,282)	(1,077,788)
Other comprehensive loss	(92,148)	(599,930)	(43,822)	(1,074,652)
Comprehensive income (loss)	171,587	(502,190)	693,684	(624,240)
Comprehensive (income) loss attributable to noncontrolling interests	(12,454)	807	(5,844)	37,930
Comprehensive income (loss) attributable to American Tower Corporation stockholders	$ 159,133	$ (501,383)	$ 687,840	$ (586,310)

CONSOLIDATED STATEMENTS OF COM7

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net change in fair value of cash flow hedges, tax benefit (expense)	$ 0	$ 9	$ 0	$ 18
Reclassification of unrealized losses on cash flow hedges to net income, tax benefit	0	20	0	66
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	108	(158)	173	(2,771)
Foreign currency translation adjustments, tax expense (benefit)	$ (1,495)	$ (12,863)	$ 5,388	$ (25,275)

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 737,506	$ 450,412
Adjustments to reconcile net income to cash provided by operating activities
Depreciation, amortization and accretion	1,137,398	932,972
Stock-based compensation expense	70,212	72,251
(Gain) loss on early retirement of long-term obligations	(830)	78,793
Other non-cash items reflected in statements of operations	120,170	143,412
Decrease in restricted cash	4,126	19,971
Increase in net deferred rent balances	(51,762)	(69,019)
Increase in assets	(8,863)	(106,535)
(Decrease) increase in liabilities	(29,526)	21,358
Cash provided by operating activities	1,978,431	1,543,615
CASH FLOWS FROM INVESTING ACTIVITIES
Payments for purchase of property and equipment and construction activities	(475,174)	(518,018)
Payments for acquisitions, net of cash acquired	(1,309,915)	(1,616,205)
Payment for Verizon transaction	(4,748)	(5,058,895)
Proceeds from sale of short-term investments and other non-current assets	4,459	1,002,214
Payments for short-term investments	0	(1,011,320)
Deposits, restricted cash, investments and other	(824)	(2,053)
Cash used for investing activities	(1,786,202)	(7,204,277)
CASH FLOW FROM FINANCING ACTIVITIES
(Repayments of) proceeds from of short-term borrowings, net	(7,337)	8,282
Borrowings under credit facilities	1,529,477	5,727,831
Proceeds from issuance of senior notes, net	3,236,383	1,492,298
Proceeds from term loan	0	500,000
Proceeds from other borrowings	70,806	0
Proceeds from issuance of securities in securitization transaction	0	875,000
Repayments of notes payable, credit facilities, senior notes, term loan and capital leases	(4,116,645)	(6,092,710)
(Distributions to) contributions from noncontrolling interest holders, net	(700)	4,449
Proceeds from stock options and ESPP	76,601	29,324
Distributions paid on common stock	(651,966)	(516,012)
Distributions paid on preferred stock	(80,344)	(57,866)
Proceeds from the issuance of common stock, net	0	2,440,327
Proceeds from the issuance of preferred stock, net	0	1,337,946
Payment for early retirement of long-term obligations	(125)	(86,107)
Deferred financing costs and other financing activities	(29,423)	(30,314)
Cash provided by financing activities	26,727	5,632,448
Net effect of changes in foreign currency exchange rates on cash and cash equivalents	(9,284)	2,126
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	209,672	(26,088)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	320,686	313,492
CASH AND CASH EQUIVALENTS, END OF PERIOD	530,358	287,404
Supplemental Cash Flow Elements [Abstract]
CASH PAID FOR INCOME TAXES (NET OF REFUNDS OF $16,219 AND $5,206, RESPECTIVELY)	71,868	130,231
CASH PAID FOR INTEREST	516,382	472,079
Decrease in accounts payable and accrued expenses for purchases of property and equipment and construction activities	(36,609)	(6,703)
Purchases of property and equipment under capital leases	37,049	19,870
Settlement of accounts receivable related to acquisitions	$ 0	$ 735

CONDENSED CONSOLIDATED STATEME9

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Statement of Cash Flows [Abstract]
Income tax refunds	$ 16,219	$ 5,206

CONSOLIDATED STATEMENTS OF EQUI

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Series B Preferred StockConvertible Preferred Stock Subject to Mandatory Redemption	Common Class A	Preferred StockSeries A Preferred StockConvertible Preferred Stock Subject to Mandatory Redemption	Preferred StockSeries B Preferred StockConvertible Preferred Stock Subject to Mandatory Redemption	Common Stock	Common StockCommon Class A	Treasury Stock	Additional Paid-in Capital	Additional Paid-in CapitalSeries B Preferred StockConvertible Preferred Stock Subject to Mandatory Redemption	Additional Paid-in CapitalCommon Class A	Accumulated Other Comprehensive Loss	Distributions in Excess of Earnings	Noncontrolling Interest	AOCI Attributable to Noncontrolling Interest
BALANCE at Dec. 31, 2014	$ 4,053,352			$ 60	$ 0	$ 3,995		$ (207,740)	$ 5,788,786			$ (794,221)	$ (837,320)	$ 99,792
BALANCE (shares) at Dec. 31, 2014				6,000,000	0	399,508,751		(2,810,026)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation related activity	79,887					$ 9			79,878
Stock based compensation related activity (shares)						904,645
Issuance of common stock	3,465								3,465
Issuance of common stock (shares)						43,940
Issuance of stock		$ 1,337,946	$ 2,440,327		$ 14		$ 259			$ 1,337,932	$ 2,440,068
Issuance of stock (shares)					1,375,000		25,850,000
Changes in fair value of cash flow hedges, net of tax	365											377		(12)
Reclassification of unrealized gains on cash flow hedges to net income	2,771											2,728		43
Foreign currency translation adjustment, net of tax	(1,077,788)											(1,041,787)		(36,001)
Contributions from noncontrolling interest holders	5,105													5,105
Distributions to noncontrolling interest holders	(656)													(656)
Common stock dividends/distributions declared	(560,993)												(560,993)
Preferred stock dividends declared	(49,991)												(49,991)
Net income	450,412												452,372	(1,960)
Net income (loss)	450,412
BALANCE at Sep. 30, 2015	6,684,202			$ 60	$ 14	$ 4,263		$ (207,740)	9,650,129			(1,832,903)	(995,932)	66,311
BALANCE (shares) at Sep. 30, 2015				6,000,000	1,375,000	426,307,336		(2,810,026)
BALANCE at Dec. 31, 2015	6,712,818			$ 60	$ 14	$ 4,267		$ (207,740)	9,690,609			(1,836,996)	(998,535)	61,139
BALANCE (shares) at Dec. 31, 2015				6,000,000	1,375,000	426,695,279		(2,810,026)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation related activity	123,376					$ 17			123,359
Stock based compensation related activity (shares)						1,691,546
Issuance of common stock	3,847								3,847
Issuance of common stock (shares)						44,733
Changes in fair value of cash flow hedges, net of tax	(367)											(367)
Reclassification of unrealized gains on cash flow hedges to net income	(173)											(173)
Foreign currency translation adjustment, net of tax	(43,282)											(38,838)		(2,306)	$ (41,144)
Contributions from noncontrolling interest holders	47													47
Distributions to noncontrolling interest holders	(747)													(747)
Common stock dividends/distributions declared	(679,002)												(679,002)
Preferred stock dividends declared	(80,344)												(80,344)
Net income	737,506												727,218	8,752
Net income (loss)	735,970
BALANCE at Sep. 30, 2016	$ 6,774,281			$ 60	$ 14	$ 4,284		$ (207,740)	$ 9,817,815			$ (1,876,374)	$ (1,030,663)	$ 66,885
BALANCE (shares) at Sep. 30, 2016				6,000,000	1,375,000	428,431,558		(2,810,026)

DESCRIPTION OF BUSINESS, BASIS

DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES American Tower Corporation (together with its subsidiaries, “ATC” or the “Company”) is one of the largest global real estate investment trusts and a leading independent owner, operator and developer of multitenant communications real estate. The Company’s primary business is the leasing of space on communications sites to wireless service providers, radio and television broadcast companies, wireless data providers, government agencies and municipalities and tenants in a number of other industries, which the Company refers to as its property operations. Additionally, the Company offers tower-related services, referred to as its services operations, in the United States, including site acquisition, zoning and permitting and structural analysis, which primarily support its site leasing business, including the addition of new tenants and equipment on its sites. The Company’s portfolio primarily consists of towers it owns and towers it operates pursuant to long-term lease arrangements, as well as distributed antenna system (“DAS”) networks, which provide seamless coverage solutions for in-building and certain outdoor wireless environments. In addition to the communications sites in its portfolio, the Company manages rooftop and tower sites for property owners under various contractual arrangements. The Company also holds property interests that it leases to communications service providers and third-party tower operators. 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. On April 21, 2016, the Company significantly expanded its Asia segment portfolio by acquiring a 51% controlling ownership interest in Viom Networks Limited (“Viom”), a telecommunications infrastructure company that owns and operates over 42,000 wireless communications towers and 200 indoor DAS networks in India (the “Viom Acquisition”). Subsequent to the closing, Viom was renamed ATC Telecom Infrastructure Private Limited (“ATC TIPL”). The Company operates as a real estate investment trust for U.S. federal income tax purposes (“REIT”). Accordingly, the Company generally is not subject to U.S. federal income taxes on income generated by its REIT operations, including the income derived from leasing space on its towers, as the Company receives a dividends paid deduction for distributions to stockholders that generally offsets its income and gains. However, the Company remains obligated to pay U.S. federal income taxes on earnings from its domestic taxable REIT subsidiaries (“TRSs”). In addition, the Company’s international assets and operations, regardless of their designation for U.S. tax purposes, 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 to be included as part of the REIT. As of September 30, 2016 , the Company’s REIT-qualified businesses included its U.S. tower leasing business, most of its operations in Costa Rica, Germany and Mexico and a majority of its services segment and indoor DAS networks business. The accompanying consolidated and condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission. The financial information included herein is unaudited. However, the Company believes that all adjustments considered necessary for a fair presentation of its financial position and results of operations for such periods have been included herein. The consolidated and condensed consolidated financial statements and related notes should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2015 (the “ 2015 Form 10-K”). The results of operations for the three and nine months ended September 30, 2016 are not necessarily indicative of the results that may be expected for the entire year. Principles of Consolidation and Basis of Presentation —The accompanying consolidated and condensed consolidated financial statements include the accounts of the Company and those entities in which it has a controlling interest. Investments in entities that the Company does not control are accounted for using the equity or cost method, depending upon the Company’s ability to exercise significant influence over operating and financial policies. All intercompany accounts and transactions have been eliminated. As of September 30, 2016 , the Company has a controlling interest in two joint ventures in Ghana and Uganda with MTN Group Limited (“MTN Group”). The joint ventures are controlled by a holding company of which a wholly owned subsidiary of the Company holds a 51% interest and a wholly owned subsidiary of MTN Group holds a 49% interest. In addition, the Company holds an approximate 75% controlling interest in a subsidiary of the Company in South Africa and the South African investors hold an approximate 25% noncontrolling interest. The Company also holds a 51% controlling interest in ATC TIPL. Significant Accounting Policies —The Company’s significant accounting policies are described in note 1 to the Company’s consolidated financial statements included in the 2015 Form 10-K. There have been no material changes to the Company’s significant accounting policies during the nine months ended September 30, 2016 . Accounting Standards Updates —In May 2014, the Financial Accounting Standards Board (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 and will become effective for the Company on January 1, 2018. Early adoption is permitted for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2016. The standard permits the use of either the retrospective or cumulative effect transition method. Leases are not included in the scope of this standard. The Company is evaluating the impact this standard will have on its financial statements. In January 2016, the FASB issued new guidance on the recognition and measurement of financial assets and financial liabilities. The guidance amends certain aspects of recognition, measurement, presentation and disclosure of financial instruments. This standard is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2017. The Company does not expect the adoption of this guidance to have a material effect on its financial statements. In February 2016, the FASB issued new guidance on the accounting for leases. The guidance amends the existing accounting standards for lease accounting, including the requirement that lessees recognize assets and liabilities for leases with terms greater than twelve months in the statement of financial position. Under the new guidance, lessor accounting is largely unchanged. This guidance is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2018. The standard is required to be applied using a modified retrospective approach for all leases existing at, or entered into after, the beginning of the earliest comparative period presented. The Company is evaluating the impact this standard will have on its financial statements. In March 2016, the FASB issued new guidance on the accounting for share-based payment transactions. The guidance amends the accounting for taxes related to stock-based compensation, including how excess tax benefits and a company’s payments for tax withholdings should be classified. This guidance is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2016. The Company early adopted this standard in the second quarter of 2016 and elected to account for forfeitures as they occur, effective January 1, 2016. The adoption of this guidance was not material to the Company’s consolidated financial statements. Additionally, the Company elected to apply the prospective transition method to the amendments related to the presentation of excess tax benefits in the statements of cash flows. In August 2016, the FASB issued new guidance on certain classifications within the statement of cash flows. The guidance addresses, among other things, how cash receipts and cash payments are presented and classified in the statement of cash flows, including payments for costs related to debt prepayments or extinguishment, as well as payments of contingent consideration after an acquisition. The guidance is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption within an interim period. The Company is evaluating the impact this standard will have on its financial statements.

PREPAID AND OTHER CURRENT ASSET

PREPAID AND OTHER CURRENT ASSETS	9 Months Ended
	Sep. 30, 2016
Prepaid Expense and Other Assets, Current [Abstract]
PREPAID AND OTHER CURRENT ASSETS	PREPAID AND OTHER CURRENT ASSETS Prepaid and other current assets consisted of the following (in thousands): As of September 30, 2016 December 31, 2015 Prepaid operating ground leases $ 129,515 $ 128,542 Prepaid income tax 109,949 45,056 Unbilled receivables 59,928 34,173 Prepaid assets 54,584 32,892 Value added tax and other consumption tax receivables 24,519 30,239 Other miscellaneous current assets 37,341 35,333 Total $ 415,836 $ 306,235

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	9 Months Ended
	Sep. 30, 2016
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 were as follows (in thousands): Property Services Total U.S. Asia (1) EMEA Latin America Balance as of January 1, 2016 $ 3,379,163 $ 170,719 $ 132,570 $ 407,365 $ 1,988 $ 4,091,805 Additions (2) — 826,735 42,297 5,008 — 874,040 Effect of foreign currency translation — (2,890 ) (19,703 ) 53,972 — 31,379 Balance as of September 30, 2016 $ 3,379,163 $ 994,564 $ 155,164 $ 466,345 $ 1,988 $ 4,997,224 _______________ (1) Includes approximately $826.7 million of goodwill assumed in the Viom Acquisition (see note 13). (2) Balances have been revised to reflect purchase accounting measurement period adjustments. The Company’s other intangible assets subject to amortization consisted of the following: As of September 30, 2016 As of December 31, 2015 Estimated Useful Lives Gross Carrying Value Accumulated Amortization Net Book Value Gross Carrying Value Accumulated Amortization Net Book Value (years) (in thousands) Acquired network location intangibles (1) Up to 20 $ 4,626,477 $ (1,229,177 ) $ 3,397,300 $ 3,980,281 $ (1,052,393 ) $ 2,927,888 Acquired customer-related intangibles 15-20 10,242,624 (2,115,242 ) 8,127,382 8,640,554 (1,763,853 ) 6,876,701 Acquired licenses and other intangibles 3-20 28,332 (4,283 ) 24,049 28,293 (5,486 ) 22,807 Economic Rights, TV Azteca 70 19,376 (10,143 ) 9,233 21,688 (11,208 ) 10,480 Total other intangible assets $ 14,916,809 $ (3,358,845 ) $ 11,557,964 $ 12,670,816 $ (2,832,940 ) $ 9,837,876 _______________ (1) 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. The acquired network location intangibles represent the value to the Company of the incremental revenue growth that could potentially be obtained from leasing the excess capacity on acquired communications sites. The acquired customer-related intangibles typically represent the value to the Company of customer contracts and relationships in place at the time of an acquisition or similar transaction, including assumptions regarding estimated renewals. The Company amortizes its acquired network location intangibles and customer-related intangibles on a straight-line basis over their estimated useful lives. As of September 30, 2016 , the remaining weighted average amortization period of the Company’s intangible assets, excluding the TV Azteca Economic Rights detailed in note 5 to the Company’s consolidated financial statements included in the 2015 Form 10-K, was 16 years. Amortization of intangible assets for the three and nine months ended September 30, 2016 was $183.9 million and $521.0 million , respectively, and amortization of intangible assets for the three and nine months ended September 30, 2015 was $154.4 million and $412.5 million , respectively. Based on current exchange rates, the Company expects to record amortization expense as follows over the remaining current year and the five subsequent years (in millions): Fiscal Year Remainder of 2016 $ 179.6 2017 716.2 2018 714.0 2019 711.1 2020 692.3 2021 682.8

ACCRUED EXPENSES

ACCRUED EXPENSES	9 Months Ended
	Sep. 30, 2016
Accrued Liabilities, Current [Abstract]
ACCRUED EXPENSES	ACCRUED EXPENSES Accrued expenses consisted of the following (in thousands): As of September 30, 2016 December 31, 2015 Accrued property and real estate taxes $ 114,839 $ 75,827 Payroll and related withholdings 63,848 62,334 Accrued rent 52,926 54,732 Accrued construction costs 19,517 19,857 Accrued income tax payable 2,480 11,704 Other accrued expenses 318,379 291,959 Total $ 571,989 $ 516,413

LONG-TERM OBLIGATIONS

LONG-TERM OBLIGATIONS	9 Months Ended
	Sep. 30, 2016
Long-term Debt, Excluding Current Maturities [Abstract]
LONG-TERM OBLIGATIONS	LONG-TERM OBLIGATIONS Outstanding amounts under the Company’s long-term obligations, reflecting discounts, premiums and debt issuance costs, consisted of the following (in thousands): As of September 30, 2016 December 31, 2015 Maturity Date Series 2013-1A securities (1) $ 498,351 $ 497,478 March 15, 2018 Series 2013-2A securities (2) 1,289,872 1,288,689 March 15, 2023 Series 2015-1 notes (3) 346,897 346,262 June 15, 2020 Series 2015-2 notes (4) 519,271 518,776 June 16, 2025 2012 GTP notes (5) 180,846 281,902 March 15, 2019 Unison notes (6) 200,616 201,930 Various Viom indebtedness (7) 593,491 — Various Viom preference shares (8) 25,021 — Various Shareholder loans (9) 151,723 145,540 Various BR Towers debentures (10) 103,194 85,219 October 15, 2023 Colombian credit facility (11) 60,131 59,640 April 24, 2021 South African facility (12) 50,911 53,175 December 17, 2020 Brazil credit facility (13) 38,900 21,868 January 15, 2022 Indian working capital facility (14) 662 8,752 October 31, 2016 Total American Tower subsidiary debt 4,059,886 3,509,231 2013 Credit Facility 137,692 1,225,000 June 28, 2019 Term Loan 994,553 1,993,601 January 29, 2021 2014 Credit Facility 1,840,000 1,980,000 January 29, 2021 4.500% senior notes 998,357 997,693 January 15, 2018 3.40% senior notes 999,661 999,769 February 15, 2019 7.25% senior notes 296,665 296,242 May 15, 2019 2.800% senior notes 744,557 743,557 June 1, 2020 5.050% senior notes 697,165 697,216 September 1, 2020 3.300% senior notes 744,465 — February 15, 2021 3.450% senior notes 643,529 642,786 September 15, 2021 5.900% senior notes 497,203 497,188 November 1, 2021 2.250% senior notes 594,903 — January 15, 2022 4.70% senior notes 695,821 695,374 March 15, 2022 3.50% senior notes 988,820 987,966 January 31, 2023 5.00% senior notes 1,002,816 1,003,453 February 15, 2024 4.000% senior notes 739,717 739,057 June 1, 2025 4.400% senior notes 495,102 — February 15, 2026 3.375% senior notes 983,007 — October 15, 2026 3.125% senior notes 396,702 — January 15, 2027 Total American Tower Corporation debt 14,490,735 13,498,902 Other debt, including capital lease obligations 128,515 110,876 Total 18,679,136 17,119,009 Less current portion of long-term obligations (242,992 ) (50,202 ) Long-term obligations $ 18,436,144 $ 17,068,807 _______________ (1) Maturity date represents anticipated repayment date; final legal maturity is March 15, 2043. (2) Maturity date represents anticipated repayment date; final legal maturity is March 15, 2048. (3) Maturity date represents anticipated repayment date; final legal maturity is June 15, 2045. (4) Maturity date represents anticipated repayment date; final legal maturity is June 15, 2050. (5) Secured debt assumed by the Company in connection with its acquisition of MIP Tower Holdings LLC. Maturity date represents anticipated repayment date; final legal maturity is March 15, 2042. During the nine months ended September 30, 2016 , the Company repaid the $94.1 million outstanding under the Secured Tower Cellular Site Revenue Notes, Series 2012-1 Class A and released 472 sites in connection with this repayment. (6) Secured debt assumed by the Company in connection with its acquisition of certain legal entities from Unison Holdings LLC and Unison Site Management II, L.L.C (together, “Unison”). In October 2016, the Company repaid the $67.0 million outstanding under the Secured Cellular Site Revenue Notes, Series 2010-1, Class C. The anticipated repayment date for the remaining series is April 15, 2020; final legal maturity date is April 15, 2040. (7) Debt primarily assumed by the Company in connection with the Viom Acquisition. Maturity dates begin March 31, 2017. Denominated in Indian Rupees (“INR”). In October 2016, ATC TIPL refinanced 3.6 billion INR ( $53.5 million as of September 30, 2016) of Viom assumed indebtedness with borrowings under a new short-term committed loan facility with a borrowing capacity of 5.8 billion INR ( $87.1 million as of September 30, 2016) and repaid an additional 1.4 billion INR ( $21.0 million as of September 30, 2016) of Viom assumed indebtedness with cash on hand. (8) Mandatorily redeemable preference shares (the “Preference Shares”) classified as debt, assumed by the Company in connection with the Viom Acquisition. The shares are to be redeemed in equal parts on March 26, 2017 and March 26, 2018. (9) Reflects balances owed to the Company’s joint venture partners in Ghana and Uganda. The Ghana loan is denominated in Ghanaian Cedi and the Uganda loan is denominated in U.S. Dollars. (10) Publicly issued debentures assumed by the Company in connection with its acquisition of BR Towers S.A. Denominated in Brazilian Reais (“BRL”). (11) Denominated in Colombian Pesos and amortizes through April 24, 2021. (12) Denominated in South African Rand and amortizes through December 17, 2020. (13) Denominated in BRL. (14) Denominated in INR. This agreement provides that the maturity date may be extended for additional 30-day periods. Current portion of long-term obligations— The Company’s current portion of long-term obligations includes (i) 7.2 billion INR ( $108.4 million ) of indebtedness primarily assumed by the Company in connection with the Viom Acquisition, (ii) 0.8 billion INR ( $12.5 million ) related to Preference Shares and (iii) $67.4 million outstanding under the Secured Cellular Site Revenue Notes, Series 2010-1, Class C (included in the Unison notes) assumed in connection with the acquisition of Unison. Viom indebtedness— Amounts outstanding and key terms of the Viom indebtedness consisted of the following as of September 30, 2016 (in millions, except percentages): Amount Outstanding (INR) Amount Outstanding (USD) Interest Rate (Range) Maturity Date (Range) Term loans 33,533 $ 503.4 10.50% - 11.20% March 31, 2017 - November 30, 2024 Debenture 6,000 $ 90.1 9.90 % April 28, 2020 Working capital facilities — — 9.85% - 11.80% October 23, 2016 - March 18, 2017 The Viom indebtedness includes several term loans, ranging from one to ten years, which are generally secured by the borrower’s short-term and long-term assets. Each of the term loans bear interest at the applicable bank’s Marginal Cost of Funds based Lending Rate or base rate, plus a spread. Interest rates on the term loans are fixed until certain annual reset dates. Generally, the term loans can be repaid without penalty on the annual reset dates; earlier repayments require notice to the lenders and are subject to prepayment penalties, typically of 1% to 2% . Scheduled repayment terms include either ratable or staggered amortization with repayments typically commencing between six and 36 months after the initial disbursement of funds. The debenture is secured by the borrower’s long-term assets, including property and equipment and intangible assets. The debenture bears interest at a base rate plus a spread of 0.6% . The base rate is set in advance for each quarterly coupon period. Should the actual base rate be between 9.75% and 10.25% , the revised base rate is assumed to be 10.00% for purposes of the reset. Additionally, the spread is subject to reset 36 and 48 months from the issuance date of April 27, 2015. The holders of the debenture must reach a consensus on the revised spread and the borrower must redeem all of the debentures held by holders from whom consensus is not achieved. Additionally, the debenture is required to be redeemed by the borrower if it does not maintain a minimum credit rating. The Viom indebtedness includes several working capital facilities, most of which are subject to annual renewal, which are generally secured by the borrower’s short-term and long-term assets. The working capital facilities bear interest at rates that are comprised of base rates plus spreads. Generally, the working capital facilities are payable on demand prior to maturity. Viom preference shares— As of September 30, 2016 , ATC TIPL had 166,666,666 Preference Shares outstanding, which are required to be redeemed in cash. Accordingly, the Company recognized debt of 1.67 billion INR ( $25.0 million ) related to the Preference Shares outstanding on the consolidated balance sheet. Unless redeemed earlier, the Preference Shares will be redeemed in two equal installments on March 26, 2017 and March 26, 2018 in an amount equal to ten INR per share along with a redemption premium, as defined in the investment agreement, which equates to a compounded return of 13.5% per annum. ATC TIPL, at its option, may redeem the Preference Shares prior to the aforementioned dates, subject to an additional 2% redemption premium. Senior Notes Offerings 3.300% Senior Notes and 4.400% Senior Notes Offering— On January 12, 2016, the Company completed a registered public offering of $750.0 million aggregate principal amount of 3.300% senior unsecured notes due 2021 (the “ 3.300% Notes”) and $500.0 million aggregate principal amount of 4.400% senior unsecured notes due 2026 (the “ 4.400% Notes”). The net proceeds from this offering were approximately $1,237.2 million , after deducting commissions and estimated expenses. The Company used the proceeds to repay existing indebtedness under its multicurrency senior unsecured revolving credit facility entered into in June 2013, as amended (the “2013 Credit Facility”), and for general corporate purposes. The 3.300% Notes will mature on February 15, 2021 and bear interest at a rate of 3.300% per annum. The 4.400% Notes will mature on February 15, 2026 and bear interest at a rate of 4.400% per annum. Accrued and unpaid interest on the notes will be payable in U.S. Dollars semi-annually in arrears on February 15 and August 15 of each year, beginning on August 15, 2016. Interest on the notes is computed on the basis of a 360-day year comprised of twelve 30-day months and commenced accruing on January 12, 2016. 3.375% Senior Notes Offering— On May 13, 2016, the Company completed a registered public offering of $1.0 billion aggregate principal amount of 3.375% senior unsecured notes due 2026 (the “ 3.375% Notes”). The net proceeds from this offering were approximately $981.5 million , after deducting commissions and estimated expenses. The Company used the proceeds to repay existing indebtedness under the 2013 Credit Facility. The 3.375% Notes will mature on October 15, 2026 and bear interest at a rate of 3.375% per annum. Accrued and unpaid interest on the notes will be payable in U.S. Dollars semi-annually in arrears on April 15 and October 15 of each year, beginning on October 15, 2016. Interest on the notes is computed on the basis of a 360-day year comprised of twelve 30-day months and commenced accruing on May 13, 2016. 2.250% Senior Notes and 3.125% Senior Notes Offering— On September 30, 2016, the Company completed a registered public offering of $600.0 million aggregate principal amount of 2.250% senior unsecured notes due 2022 (the “ 2.250% Notes”) and $400.0 million aggregate principal amount of 3.125% senior unsecured notes due 2027 (the “ 3.125% Notes”). The net proceeds from this offering were approximately $990.6 million , after deducting commissions and estimated expenses. The Company used the proceeds to repay existing indebtedness under the Company’s unsecured term loan entered into in October 2013, as amended (the “Term Loan”). The 2.250% Notes will mature on January 15, 2022 and bear interest at a rate of 2.250% per annum. The 3.125% Notes will mature on January 15, 2027 and bear interest at a rate of 3.125% per annum. Accrued and unpaid interest on the notes will be payable in U.S. Dollars semi-annually in arrears on January 15 and July 15 of each year, beginning on January 15, 2017. Interest on the notes is computed on the basis of a 360-day year comprised of twelve 30-day months and commenced accruing on September 30, 2016. The Company entered into interest rate swaps, which were designated as fair value hedges at inception, to hedge against changes in fair value of the debt under the 2.250% Notes resulting from changes in interest rates. As of September 30, 2016, the interest rate on the 2.250% Notes, after giving effect to the interest rate swap agreements, was 1.75% . The Company may redeem each series of notes at any time, in whole or in part, at a redemption price equal to 100% of the principal amount of the notes plus a make-whole premium, together with accrued interest to the redemption date. If the Company redeems the 3.300% Notes on or after January 15, 2021, the 4.400% Notes on or after November 15, 2025, the 3.375% Notes on or after July 15, 2026 or the 3.125% Notes on or after October 15, 2026, it will not be required to pay a make-whole premium. In addition, if the Company undergoes a change of control and corresponding ratings decline, each as defined in the applicable supplemental indenture, it may be required to repurchase all of the applicable notes at a purchase price equal to 101% of the principal amount of such notes, plus accrued and unpaid interest (including additional interest, if any), up to but not including the repurchase date. 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 its subsidiaries. The supplemental indentures 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 does not exceed 3.5 x Adjusted EBITDA, as defined in the applicable supplemental indenture. Bank Facilities 2013 Credit Facility— During the nine months ended September 30, 2016 , the Company borrowed an aggregate of $1.4 billion and repaid an aggregate of $2.5 billion of revolving indebtedness under the 2013 Credit Facility. The Company primarily used the borrowings to fund the Viom Acquisition. 2014 Credit Facility— During the nine months ended September 30, 2016 , the Company borrowed an aggregate of $80.0 million and repaid an aggregate of $220.0 million of revolving indebtedness under its senior unsecured revolving credit facility entered into in January 2012 and amended and restated in September 2014, as further amended (the “2014 Credit Facility”). On October 17, 2016, the Company borrowed an additional $140.0 million under the 2014 Credit Facility. Term Loan— During the nine months ended September 30, 2016 , the Company repaid $1.0 billion of indebtedness under the Term Loan. As of September 30, 2016 , the key terms under the 2013 Credit Facility, the 2014 Credit Facility and the Term Loan were as follows: Outstanding Principal Balance (in millions) Undrawn letters of credit (in millions) Maturity Date Current margin over LIBOR (1) Current commitment fee (2) 2013 Credit Facility $ 137.7 $ 3.2 June 28, 2019 (3) 1.250 % 0.150 % 2014 Credit Facility $ 1,840.0 $ 7.4 January 29, 2021 (3) 1.250 % 0.150 % Term Loan $ 1,000.0 $ — January 29, 2021 1.250 % N/A _______________ (1) LIBOR means the London Interbank Offered Rate. (2) Fee on undrawn portion of each credit facility. (3) Subject to two optional renewal periods.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	9 Months Ended
	Sep. 30, 2016
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 values of the Company’s financial assets and liabilities that are required to be measured on a recurring basis at fair value were as follows (in thousands): September 30, 2016 December 31, 2015 Fair Value Measurements Using Fair Value Measurements Using Level 2 Level 3 Level 2 Level 3 Assets: Interest rate swap agreements $ 212 — $ 692 — Embedded derivative in lease agreement — $ 13,513 — $ 14,176 Liabilities: Acquisition-related contingent consideration — $ 21,575 — $ 12,436 On September 30, 2016, the Company entered into interest rate swap agreements with an aggregate notional value of $600.0 million related to the 2.250% Notes. The interest rate swap agreements require the Company to pay interest at a variable interest rate of one-month LIBOR plus applicable spreads and to receive fixed interest at a rate of 2.250% through January 15, 2022. During the nine months ended September 30, 2016 , the Company has made no changes to the methods described in note 11 to the Company’s consolidated financial statements in the 2015 Form 10-K that it used to measure the fair value of its interest rate swap agreements, the embedded derivative in one of its lease agreements and acquisition-related contingent consideration. The changes in fair value during the nine months ended September 30, 2016 and 2015 were not material to the consolidated financial statements. As of September 30, 2016 , the Company estimated the value of all potential acquisition-related contingent consideration required payments to be between zero and $47.7 million , which includes $22.2 million related to an acquisition in South Africa that occurred during the three months ended September 30, 2016. Redeemable Noncontrolling Interests In connection with the Viom Acquisition, the Company entered into a shareholders’ agreement that provides for put options held by certain noncontrolling shareholders. The fair value of the Company’s noncontrolling interests reflected on the consolidated balance sheet are determined using a discounted cash flow approach, which takes into consideration Level 3 unobservable inputs and applies a discount factor. The fair value of the redeemable noncontrolling interests was $1.1 billion at the date of acquisition and was recorded in Redeemable noncontrolling interests in the consolidated balance sheet. See notes 9 and 13 for more information. Items Measured at Fair Value on a Nonrecurring Basis Assets Held and Used —The Company’s long-lived assets are recorded at amortized cost and, if impaired, are adjusted to fair value using Level 3 inputs. During the three and nine months ended September 30, 2016 and 2015, the Company did not record any material asset impairment charges. There were no other items measured at fair value on a nonrecurring basis during the nine months ended September 30, 2016 and 2015. Fair Value of Financial Instruments —The Company’s financial instruments for which the carrying value reasonably approximates fair value at September 30, 2016 and December 31, 2015 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 September 30, 2016 and December 31, 2015 , the carrying value of long-term obligations, including the current portion, was $18.7 billion and $17.1 billion , respectively. As of September 30, 2016 , the fair value of long-term obligations, including the current portion, was $19.5 billion , of which $12.3 billion was measured using Level 1 inputs and $7.2 billion was measured using Level 2 inputs. As of December 31, 2015 , the fair value of long-term obligations, including the current portion, was $17.4 billion , of which $8.7 billion was measured using Level 1 inputs and $8.7 billion was measured using Level 2 inputs.

INCOME TAXES

INCOME TAXES	9 Months Ended
	Sep. 30, 2016
Income Tax Expense (Benefit), Continuing Operations [Abstract]
INCOME TAXES	INCOME TAXES The Company provides for income taxes at the end of each interim period based on the estimated effective tax rate (“ETR”) for the full fiscal year. Cumulative adjustments to the Company’s estimate are recorded in the interim period in which a change in the estimated annual ETR is determined. As a REIT, the Company continues to be subject to income taxes on the income of its TRSs and income taxes in foreign jurisdictions where it conducts operations. Under the provisions of the Internal Revenue Code of 1986, as amended, the Company may deduct amounts distributed to stockholders against the income generated by its REIT operations. In addition, the Company is able to offset certain income by utilizing its net operating losses, subject to specified limitations. The Company provides valuation allowances if, based on the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. Management assesses the available positive and negative evidence to estimate if sufficient future taxable income will be generated to use the existing deferred tax assets. As described in note 1, effective January 1, 2016, the Company adopted new guidance on the accounting for share-based payment transactions. As part of this new guidance, excess windfall tax benefits and tax deficiencies related to the Company’s stock option exercises and restricted stock unit vestings are recognized as an income tax benefit or expense in the consolidated statements of operations in the period in which the deduction occurs. Excess windfall tax benefits and tax deficiencies are, therefore, not anticipated when determining the annual ETR and are instead recognized in the interim period in which those items occur. As of September 30, 2016 and December 31, 2015 , the total unrecognized tax benefits that would impact the ETR, if recognized, were approximately $74.7 million and $28.1 million , respectively. The amount of unrecognized tax benefits during the three and nine months ended September 30, 2016 includes additions to the Company’s existing tax positions of $8.4 million and $47.7 million (including $23.8 million assumed through acquisition), respectively, and reductions due to the expiration of the statute of limitations in certain jurisdictions of $1.8 million during each of the three and nine months ended September 30, 2016 . 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 time frame, as described in note 12 to the Company’s consolidated financial statements included in the 2015 Form 10-K. The impact of the amount of these changes to previously recorded uncertain tax positions could range from zero to $12.4 million . The Company recorded penalties and income tax-related interest expense during the three and nine months ended September 30, 2016 of $1.8 million and $7.0 million , respectively, and during the three and nine months ended September 30, 2015 of $0.7 million and $2.3 million , respectively. In addition, due to the expiration of the statute of limitations in certain jurisdictions, the Company reduced its liability for penalties and income tax-related interest expense related to uncertain tax positions during the three and nine months ended September 30, 2016 by $1.6 million and during the three and nine months ended September 30, 2015 by $3.1 million . As of September 30, 2016 and December 31, 2015 , the total amount of accrued income tax related interest and penalties included in the consolidated balance sheets was $24.5 million and $20.2 million , respectively.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	9 Months Ended
	Sep. 30, 2016
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION 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, generally over four years for time-based restricted stock units (“RSUs”) and stock options and three years for performance-based restricted stock units (“PSUs”). Stock options generally expire ten years from the date of grant. As of September 30, 2016 , the Company had the ability to grant stock-based awards with respect to an aggregate of 9.5 million shares of common stock under the 2007 Plan. In addition, the Company maintains an employee stock purchase plan (“ESPP”) pursuant to which eligible employees may purchase shares of the Company’s common stock on the last day of each bi-annual offering period at a 15% discount of the lower of the closing market value on the first or last day of such offering period. The offering periods run from June 1 through November 30 and from December 1 through May 31 of each year. During the three and nine months ended September 30, 2016 and 2015 , the Company recorded and capitalized the following stock-based compensation expenses (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Stock-based compensation expense $ 20,226 $ 18,345 $ 70,212 $ 72,251 Stock-based compensation expense capitalized as property and equipment $ 353 $ 495 $ 1,115 $ 1,554 Stock Options —The fair value of each option granted during the nine months ended September 30, 2016 was estimated on the date of grant using the Black-Scholes option pricing model based on the assumptions noted in the table below. The expected life of stock options (estimated period of time outstanding) was estimated using the vesting term and historical exercise behavior of the Company’s employees. The risk-free interest rate was based on the U.S. Treasury yield with a term that approximated the estimated life in effect at the accounting measurement date. The expected volatility of the underlying stock price was based on historical volatility for a period equal to the expected life of the stock options. The expected annual dividend yield was the Company’s best estimate of expected future dividend yield. Key assumptions used to apply this pricing model during the nine months ended September 30, 2016 were as follows: Range of risk-free interest rate 1.00% - 1.73% Weighted average risk-free interest rate 1.45% Range of expected life of stock options 4.5 - 5.2 years Range of expected volatility of the underlying stock price 20.64% - 21.45% Weighted average expected volatility of underlying stock price 21.45% Range of expected annual dividend yield 1.85% - 2.40% The weighted average grant date fair value per share during the nine months ended September 30, 2016 was $14.57 . As of September 30, 2016 , total unrecognized compensation expense related to unvested stock options was $30.1 million , which is expected to be recognized over a weighted average period of approximately two years . The Company’s option activity for the nine months ended September 30, 2016 was as follows: Number of Options Outstanding as of January 1, 2016 7,680,819 Granted 1,140,366 Exercised (1,263,309 ) Forfeited (16,320 ) Expired (800 ) Outstanding as of September 30, 2016 7,540,756 Restricted Stock Units— As of September 30, 2016 , total unrecognized compensation expense related to unvested RSUs granted under the 2007 Plan was $100.6 million and is expected to be recognized over a weighted average period of approximately two years . Performance-Based Restricted Stock Units— During the nine months ended September 30, 2016 , the Company’s Compensation Committee granted an aggregate of 169,340 PSUs to its executive officers (the “2016 PSUs”) and established the performance metrics for this award. During the nine months ended September 30, 2015 , the Company’s Compensation Committee granted an aggregate of 70,135 PSUs to its executive officers (the “2015 PSUs”) and established the performance metric for this award. Threshold, target and maximum parameters were established for the metrics for a three -year performance period with respect to the 2016 PSUs and for each year in the three -year performance period with respect to the 2015 PSUs and will be used to calculate the number of shares that will be issuable when the award vests, which may range from zero to 200% of the target amount. At the end of the three -year performance period, the number of shares that vest will depend on the degree of achievement against the pre-established performance goals. PSUs will be paid out in common stock at the end of the performance period, subject generally to the executive’s continued employment. PSUs will accrue dividend equivalents prior to vesting, which will be paid out only in respect of shares actually vested. The performance metric related to the 2015 PSUs is tied to year-over-year growth, and actual results for the metric cannot be determined until the end of each respective fiscal year. As a result, as of September 30, 2016 , the Company was unable to determine the annual target for the third year of the performance period for this award. Accordingly, an aggregate of 23,377 PSUs was not included in the table below. Restricted Stock Units and Performance-Based Restricted Stock Units —The Company’s RSU and PSU activity for the nine months ended September 30, 2016 was as follows: RSUs PSUs Outstanding as of January 1, 2016 (1) 1,656,993 33,377 Granted (2) 774,739 192,719 Vested (641,810 ) — Forfeited (84,461 ) — Outstanding as of September 30, 2016 1,705,461 226,096 _______________ (1) PSUs represent the shares issuable for the 2015 PSUs at the end of the three -year performance cycle based on exceeding the performance metric for the first year’s performance period. (2) PSUs represent the target number of shares issuable at the end of the three -year performance cycle attributable to the second year’s performance period for the 2015 PSUs and the target number of shares issuable at the end of the three -year performance cycle for the 2016 PSUs. During the three and nine months ended September 30, 2016 , the Company recorded $2.3 million and $5.5 million , respectively, in stock-based compensation expense for equity awards in which the performance goals had been established and were probable of being achieved. The remaining unrecognized compensation expense related to these awards at September 30, 2016 was $14.2 million based on the Company’s current assessment of the probability of achieving the performance goals. The weighted-average period over which the cost will be recognized is approximately two years .

REDEEMABLE NONCONTROLLING INTER

REDEEMABLE NONCONTROLLING INTERESTS	9 Months Ended
	Sep. 30, 2016
Noncontrolling Interest [Abstract]
REDEEMABLE NONCONTROLLING INTERESTS	REDEEMABLE NONCONTROLLING INTERESTS Redeemable Noncontrolling Interests —In connection with the Viom Acquisition, the Company, through one of its subsidiaries, entered into a shareholders agreement (the “Shareholders Agreement”) with Viom and the following remaining Viom shareholders: Tata Sons Limited, Tata Teleservices Limited, IDFC Private Equity Fund III, Macquarie SBI Investments Pte Limited and SBI Macquarie Infrastructure Trust (collectively, the “Remaining Shareholders”). The Shareholders Agreement provides for, among other things, put options held by certain of the Remaining Shareholders, which allow the Remaining Shareholders to sell outstanding shares of ATC TIPL, and call options held by the Company, which allow the Company to buy the noncontrolling shares of ATC TIPL. The put options, which are not under the Company’s control, cannot be separated from the noncontrolling interests. As a result, the combination of the noncontrolling interests and the redemption feature require classification as redeemable noncontrolling interests in the consolidated balance sheet, separate from equity. Given the provisions governing the put rights, the redeemable noncontrolling interests are recorded outside of permanent equity at their redemption value. The noncontrolling interests become redeemable after the passage of time, and therefore, the Company records the carrying amount of the noncontrolling interests at the greater of (i) the initial carrying amount, increased or decreased for the noncontrolling interests’ share of net income or loss and foreign currency translation adjustments, and (ii) the redemption value. If required, the Company will adjust the redeemable noncontrolling interests to redemption value on each balance sheet date with changes in redemption value recognized as an adjustment to Distributions in excess of earnings. The put options may be exercised, requiring the Company to purchase the Remaining Shareholders’ equity interests, on specified dates beginning April 1, 2018 through March 31, 2021. The price of the put options will be based on the fair market value of the exercising Remaining Shareholder’s interest in the Company’s India operations at the time the option is exercised. Put options held by certain of the Remaining Shareholders are subject to a floor price of 216 INR per share. The following is a reconciliation of the changes in the Redeemable noncontrolling interests (in thousands): Balance as of January 1, 2016 $ — Fair value at acquisition 1,100,804 Net income attributable to noncontrolling interests 1,536 Foreign currency translation adjustment attributable to noncontrolling interests (2,138 ) Balance as of September 30, 2016 $ 1,100,202

EQUITY

EQUITY	9 Months Ended
	Sep. 30, 2016
Stockholders' Equity Attributable to Parent [Abstract]
EQUITY	EQUITY Series A Preferred Stock —The Company has 6,000,000 shares of its 5.25% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share (the “Series A Preferred Stock”) outstanding, which were issued in May 2014. Unless converted or redeemed earlier, each share of the Series A Preferred Stock will automatically convert on May 15, 2017, into between 0.9272 and 1.1591 shares of the Company’s common stock, depending on the applicable market value of the Company’s common stock and subject to anti-dilution adjustments. Subject to certain restrictions, at any time prior to May 15, 2017, holders of the Series A 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 the Series A Preferred Stock are payable on a cumulative basis when, as and if declared by the Company’s Board of Directors 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. Series B Preferred Stock —The Company has 13,750,000 depositary shares, each representing a 1/10th interest in a share of its 5.50% Mandatory Convertible Preferred Stock, Series B, par value $0.01 per share (the “Series B Preferred Stock” and, together with the Series A Preferred Stock, the “Mandatory Convertible Preferred Stock”) outstanding, which were issued in March 2015. Unless converted or redeemed earlier, each share of the Series B Preferred Stock will automatically convert on February 15, 2018, into between 8.5911 and 10.3093 shares of the Company’s common stock, depending on the applicable market value of the Company’s common stock and subject to anti-dilution adjustments. Subject to certain restrictions, at any time prior to February 15, 2018, holders of the Series B 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 the Series B Preferred Stock are payable on a cumulative basis when, as and if declared by the Company’s Board of Directors at an annual rate of 5.50% on the liquidation preference of $1,000.00 per share (and, correspondingly, $100.00 per share with respect to the depositary shares) on February 15, May 15, August 15 and November 15 of each year, commencing on May 15, 2015 to, and including, February 15, 2018. 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. Sales of Equity Securities —The Company receives proceeds from the sale of its equity securities pursuant to its ESPP and upon exercise of stock options granted under its equity incentive plan. During the nine months ended September 30, 2016 , the Company received an aggregate of $76.6 million in proceeds upon exercises of stock options and from the ESPP. Distributions —During the nine months ended September 30, 2016 , the Company declared or paid the following cash distributions: Declaration Date Payment Date Record Date Distribution per share Aggregate Payment Amount (in millions) Common Stock December 3, 2015 January 13, 2016 December 16, 2015 $ 0.49 $ 207.7 March 9, 2016 April 28, 2016 April 12, 2016 $ 0.51 $ 216.5 June 2, 2016 July 15, 2016 June 17, 2016 $ 0.53 $ 225.4 September 16, 2016 October 17, 2016 September 30, 2016 $ 0.55 $ 234.1 Series A Preferred Stock January 14, 2016 February 16, 2016 February 1, 2016 $ 1.3125 $ 7.9 April 16, 2016 May 16, 2016 May 1, 2016 $ 1.3125 $ 7.9 July 22, 2016 August 15, 2016 August 1, 2016 $ 1.3125 $ 7.9 Series B Preferred Stock January 14, 2016 February 16, 2016 February 1, 2016 $ 13.75 $ 18.9 April 16, 2016 May 16, 2016 May 1, 2016 $ 13.75 $ 18.9 July 22, 2016 August 15, 2016 August 1, 2016 $ 13.75 $ 18.9 The Company accrues distributions on unvested restricted stock units, which are payable upon vesting. As of September 30, 2016 , the amount accrued for distributions payable related to unvested restricted stock units was $5.8 million . During the nine months ended September 30, 2016 , the Company paid $2.4 million of distributions 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 subject to adjustment, by the Company’s Board of Directors.

EARNINGS PER COMMON SHARE

EARNINGS PER COMMON SHARE	9 Months Ended
	Sep. 30, 2016
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 (in thousands, except per share data): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Net income attributable to American Tower Corporation stockholders $ 264,509 $ 102,999 $ 727,218 $ 452,372 Dividends on preferred stock (26,781 ) (26,781 ) (80,344 ) (63,382 ) Net income attributable to American Tower Corporation common stockholders 237,728 76,218 646,874 388,990 Basic weighted average common shares outstanding 425,517 423,375 424,831 417,280 Dilutive securities 4,408 3,852 4,188 4,072 Diluted weighted average common shares outstanding 429,925 427,227 429,019 421,352 Basic net income attributable to American Tower Corporation common stockholders per common share $ 0.56 $ 0.18 $ 1.52 $ 0.93 Diluted net income attributable to American Tower Corporation common stockholders per common share $ 0.55 $ 0.18 $ 1.51 $ 0.92 Shares Excluded From Dilutive Effect —The following shares were not included in the computation of diluted earnings per share because the effect would be anti-dilutive (in thousands, on a weighted average basis): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Restricted stock awards — — 2 — Stock options 8 1,996 1,619 1,472 Preferred stock 17,473 17,368 17,473 14,724

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Litigation —The Company periodically becomes involved in various claims, lawsuits and proceedings that are incidental to its business. In the opinion of Company management, after consultation with counsel, there are no matters currently pending that would, in the event of an adverse outcome, materially impact the Company’s consolidated financial position, results of operations or liquidity. Verizon Transaction —In March 2015, the Company entered into an agreement with various operating entities of Verizon Communications Inc. (“Verizon”) that provides for the lease, sublease or management of 11,286 wireless communications sites commencing March 27, 2015. The average term of the lease or sublease for all sites at the inception of the agreement was approximately 28 years , assuming renewals or extensions of the underlying ground leases for the sites. The Company has the option to purchase the leased sites in tranches, subject to the applicable lease, sublease or management rights upon its scheduled expiration. Each tower is assigned to an annual tranche, ranging from 2034 to 2047, which represents the outside expiration date for the sublease rights to the towers in that tranche. The purchase price for each tranche is a fixed amount stated in the lease for such tranche plus the fair market value of certain alterations made to the related towers. The aggregate purchase option price for the towers leased and subleased is approximately $5.0 billion . Verizon will occupy the sites as a tenant for an initial term of ten years with eight optional successive five -year terms; each such term shall be governed by standard master lease agreement terms established as a part of the transaction. 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 2,370 towers commencing between December 2000 and August 2004. Substantially all of the towers are part of the Company’s 2013 securitization transaction. The average term of the lease or sublease for all sites at the inception of the agreement was approximately 27 years , assuming renewals or extensions of the underlying ground leases for the sites. 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 lease for that site plus the fair market value of certain alterations made to the related tower by AT&T. As of September 30, 2016 , the Company has purchased an aggregate of 60 of the subleased towers upon expiration of the applicable agreement. The aggregate purchase option price for the remaining towers leased and subleased is $748.3 million and will accrete at a rate of 10% per annum through the applicable expiration of the lease or sublease of a site. For all such sites purchased by the Company prior to June 30, 2020, AT&T will continue to lease the reserved space at the then-current monthly fee, which shall escalate in accordance with the standard master lease agreement for the remainder of AT&T’s tenancy. Thereafter, AT&T shall have the right to renew such lease for up to four successive five -year terms. For all such sites purchased by the Company subsequent to June 30, 2020, AT&T has the right to continue to lease the reserved space for successive one -year terms at a rent equal to the lesser of the agreed upon market rate or the then-current monthly fee, which is subject to an annual increase based on changes in the U.S. Consumer Price Index. 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. The Company exercised the purchase options for approximately 1,525 towers in a single closing to occur on or before November 30, 2016. The Company has provided notice to the tower owner of its intent to exercise the purchase options related to the remaining towers. As of September 30, 2016 , the purchase price per tower was $42,844 payable in cash or, at Verizon Wireless’s or its assignee’s option, as applicable, with 769 shares of the Company’s common stock per tower. The aggregate cash purchase option price for the subleased towers was $75.7 million as of September 30, 2016 . 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. 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 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 September 30, 2016 were as follows (in millions): Remainder of 2016 $ 1,271 2017 4,710 2018 4,543 2019 4,269 2020 3,916 Thereafter 13,825 Total $ 32,534 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 a consumer price index 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 September 30, 2016 are as follows (in millions): Remainder of 2016 $ 244 2017 912 2018 886 2019 854 2020 815 Thereafter 7,370 Total $ 11,081

ACQUISITIONS

ACQUISITIONS	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
ACQUISITIONS	ACQUISITIONS 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 three and nine months ended September 30, 2016 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 depend on, 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 instead have been utilized solely by the seller as a component of its network infrastructure. An acquisition may or may not involve the transfer of business operations or employees. The estimated aggregate impact of the 2016 acquisitions on the Company’s revenues and gross margin for the three months ended September 30, 2016 was approximately $208.1 million and $87.9 million , respectively, and the estimated aggregate impact for the nine months ended September 30, 2016 was approximately $366.1 million and $153.1 million , respectively. The revenues and gross margin amounts also reflect incremental revenues from the addition of new tenants to such sites subsequent to the transaction date. For those acquisitions accounted for as business combinations, the Company recognizes acquisition and merger related expenses in the period in which they are incurred and services are received. Acquisition and merger related expenses 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. Integration costs include incremental and non-recurring costs necessary to convert data, retain employees and otherwise enable the Company to operate new businesses efficiently. The Company records acquisition and merger related expenses, as well as integration costs, in Other operating expenses in the consolidated statements of operations. During the three and nine months ended September 30, 2016 and 2015 , the Company recorded acquisition and merger related expenses and integration costs as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Acquisition and merger related expenses $ 1,124 $ 8,587 $ 7,844 $ 16,574 Integration costs $ 1,846 $ 5,938 $ 8,351 $ 12,218 The acquisitions described below are accounted for as business combinations and are consistent with the Company’s strategy to expand in selected geographic areas. 2016 Acquisitions Viom Acquisition— On April 21, 2016, the Company, through its wholly owned subsidiary, ATC Asia Pacific Pte. Ltd. (“ATC Asia”), acquired a 51% controlling ownership interest in Viom, a telecommunications infrastructure company that owns and operates over 42,000 wireless communications towers and 200 indoor DAS networks in India, from certain Viom shareholders, including the managing shareholder, SREI Infrastructure Finance Limited, several other minority shareholders and Tata Teleservices Limited, pursuant to its previously announced share purchase agreement. Consideration for the acquisition included 76.4 billion INR in cash ( $1.1 billion at the date of acquisition), as well as the assumption of approximately 52.3 billion INR ( $0.8 billion at the date of acquisition) of existing debt, which included 1.7 billion INR ( $25.1 million at the date of acquisition) of mandatorily redeemable preference shares issued by Viom. On April 21, 2016, the closing date of the Viom Acquisition, ATC Asia’s Shareholders Agreement with the Remaining Shareholders became effective. The Shareholders Agreement provides that, among other things, the Remaining Shareholders will have certain governance, anti-dilution and contractual rights. The Remaining Shareholders will have put options, and ATC Asia will have a call option, subject to the time periods and conditions outlined in the Shareholders Agreement. Other Acquisitions— During the nine months ended September 30, 2016 , the Company acquired a total of 784 communications sites in the United States, Brazil, Germany, Nigeria and South Africa for an aggregate purchase price of $185.6 million (including contingent consideration of $8.7 million ). Of the total purchase price, $2.1 million is reflected in Accounts payable in the condensed consolidated balance sheet as of September 30, 2016. The purchase prices of certain transactions are subject to post-closing adjustments. The following table summarizes the preliminary allocation of the purchase price for the fiscal year 2016 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Balances are reflected in the accompanying consolidated balance sheet as of September 30, 2016 . Asia Other Viom Current assets $ 281,888 $ 12,619 Non-current assets 37,737 145 Property and equipment 707,560 46,026 Intangible assets (1): Customer-related intangible assets 1,435,164 86,779 Network location intangible assets 691,484 21,258 Current liabilities (181,101 ) (7,701 ) Deferred tax liability (657,810 ) (14,290 ) Other non-current liabilities (105,458 ) (6,477 ) Net assets acquired 2,209,464 138,359 Goodwill (2) 826,735 47,200 Fair value of net assets acquired 3,036,199 185,559 Debt assumed (786,889 ) — Redeemable noncontrolling interests (1,100,804 ) — Purchase Price $ 1,148,506 $ 185,559 _______________ (1) Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years . (2) Primarily results from purchase accounting adjustments, which are not deductible for tax purposes in any foreign jurisdiction. 2015 Acquisitions The estimates of the fair value of the assets or rights 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 applicable acquisition date). During the nine months ended September 30, 2016 , the Company adopted new guidance on the accounting for measurement-period adjustments related to business combinations. This guidance requires that an acquirer make adjustments to the provisional amounts recognized at acquisition date with a corresponding adjustment to goodwill in the current period. Additionally, the effects on earnings of all measurement-period adjustments are included in current period earnings. During the nine months ended September 30, 2016 , post-closing adjustments impacted the following 2015 acquisitions: TIM Acquisition— On April 29, 2015, the Company acquired 4,176 communications sites from TIM Celular S.A. (“TIM”) for an initial aggregate purchase price of $644.3 million , which was subsequently reduced by $0.8 million during the nine months ended September 30, 2016. On September 30, 2015, the Company acquired an additional 1,125 communications sites from TIM for an initial aggregate purchase price of $130.9 million . On December 16, 2015, the Company acquired an additional 182 communications sites from TIM for an initial aggregate purchase price of $21.7 million . The purchase price for the December 2015 TIM acquisition remains subject to post-closing adjustments. Pursuant to the terms of the agreement, the Company has the ability to purchase the remaining communications sites as they become available through October 2016, a portion of which was acquired during the nine months ended September 30, 2016. Other— The initial aggregate purchase price of other 2015 acquisitions was subsequently reduced by $0.2 million during the nine months ended September 30, 2016. The following table summarizes the preliminary and updated allocations of the purchase prices paid and the amounts of assets acquired and liabilities assumed for the fiscal year 2015 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Preliminary Allocation Updated Allocation Latin America Other Latin America Other TIM TIM (1) Current assets $ — $ 1,113 $ — $ 1,113 Non-current assets — 995 — 995 Property and equipment 275,630 42,716 274,530 42,716 Intangible assets (2): Customer-related intangible assets 361,822 63,001 361,765 62,832 Network location intangible assets 115,562 37,691 115,795 37,691 Current liabilities (3,192 ) (624 ) (3,192 ) (624 ) Deferred tax liability — — — — Other non-current liabilities (74,966 ) (4,028 ) (74,966 ) (4,028 ) Net assets acquired 674,856 140,864 673,932 140,695 Goodwill 122,011 24,011 122,116 24,011 Fair value of net assets acquired 796,867 164,875 796,048 164,706 Debt assumed — — — — Purchase Price $ 796,867 $ 164,875 $ 796,048 $ 164,706 _______________ (1) The allocation of the purchase price related to the 5,301 communications sites acquired from TIM on April 29, 2015 and September 30, 2015 was finalized during the nine months ended September 30, 2016. (2) Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years . Pro Forma Consolidated Results The following table presents the unaudited pro forma financial results as if the 2016 acquisitions had occurred on January 1, 2015 and acquisitions completed in 2015 had occurred on January 1, 2014. The pro forma results do not include any anticipated cost synergies, costs or other integration impacts. Accordingly, such pro forma amounts are not necessarily indicative of the results that actually would have occurred had the transactions been completed on the date indicated, nor are they indicative of the future operating results of the Company. Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Pro forma revenues $ 1,517,197 $ 1,449,460 $ 4,498,458 $ 4,372,304 Pro forma net income attributable to American Tower Corporation common stockholders $ 238,364 $ 72,885 $ 643,780 $ 346,097 Pro forma net income per common share amounts: Basic net income attributable to American Tower Corporation common stockholders $ 0.56 $ 0.17 $ 1.52 $ 0.82 Diluted net income attributable to American Tower Corporation common stockholders $ 0.55 $ 0.17 $ 1.50 $ 0.81 Other Signed Acquisitions Airtel Tanzania— On March 17, 2016, the Company entered into a definitive agreement with Airtel, through its subsidiary company Airtel Tanzania Limited (“Airtel Tanzania”), pursuant to which the Company may acquire approximately 1,350 of Airtel Tanzania’s communications sites in Tanzania, for total consideration of approximately $179.0 million , subject to customary adjustments. Under the definitive agreement, the Company may pay additional consideration to acquire up to approximately 100 additional communications sites currently in development. The closing of this transaction is subject to customary closing conditions. In light of recent legislation in Tanzania, the Company is negotiating potential adjustments to the definitive agreement in the event a waiver of such legislation is not obtained.

BUSINESS SEGMENTS

BUSINESS SEGMENTS	9 Months Ended
	Sep. 30, 2016
Segment Reporting, Measurement Disclosures [Abstract]
BUSINESS SEGMENTS	BUSINESS SEGMENTS In 2015, as a result of recent investment activity, including signed acquisitions, the Company reviewed and changed its reportable segments to divide its international segment into three regional segments: (i) Asia property, (ii) Europe, Middle East and Africa (“EMEA”) property and (iii) Latin America property, resulting in five total segments. The change in reportable segments had no impact on the Company’s consolidated and condensed consolidated financial statements for any periods. However, certain expenses previously reflected in segment selling, general, administrative and development expense have been reclassified and are now reflected as Other selling, general, administrative and development expense. Historical financial information included in this Quarterly Report on Form 10-Q has been adjusted to reflect the change in reportable segments. The Company’s primary business is leasing space on multitenant communications sites to wireless service providers, radio and television broadcast companies, wireless data providers, government agencies and municipalities and tenants in a number of other industries. This business is referred to as the Company’s property operations, which as of September 30, 2016 , consisted of the following: • U.S.: property operations in the United States; • Asia: property operations in India; • EMEA: property operations in Germany, Ghana, Nigeria, South Africa and Uganda; and • Latin America: property operations in Brazil, Chile, Colombia, Costa Rica, Mexico and Peru. The Company has applied the aggregation criteria to operations within the EMEA and Latin America property operating segments on a basis that is consistent with management’s review of information and performance evaluations of these regions. The Company’s 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, including the addition of new tenants and equipment on its sites. The services segment is a strategic business unit that offers different services from, and requires different resources, skill sets and marketing strategies than, the property operating segments. The accounting policies applied in compiling segment information below are similar to those described in note 1 to the Company’s consolidated financial statements included in the 2015 Form 10-K. 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 Latin America property 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 interests 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 three and nine months ended September 30, 2016 and 2015 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, as the amounts are not utilized in assessing each segment’s performance. Property Total Property Services Other Total Three Months Ended September 30, 2016 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 837,002 $ 269,907 $ 130,664 $ 260,363 $ 1,497,936 $ 16,909 $ 1,514,845 Segment operating expenses (1) 188,777 154,139 53,787 88,396 485,099 5,540 490,639 Interest income, TV Azteca, net — — — 2,742 2,742 — 2,742 Segment gross margin 648,225 115,768 76,877 174,709 1,015,579 11,369 1,026,948 Segment selling, general, administrative and development expense (1) 35,526 15,030 12,958 15,454 78,968 2,726 81,694 Segment operating profit $ 612,699 $ 100,738 $ 63,919 $ 159,255 $ 936,611 $ 8,643 $ 945,254 Stock-based compensation expense $ 20,226 20,226 Other selling, general, administrative and development expense 30,215 30,215 Depreciation, amortization and accretion 397,999 397,999 Other expense (2) 211,042 211,042 Income from continuing operations before income taxes $ 285,772 Total assets $ 18,837,629 $ 4,612,766 $ 2,120,592 $ 4,885,066 $ 30,456,053 $ 60,810 $ 138,664 $ 30,655,527 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.6 million and $19.6 million , respectively. (2) Primarily includes interest expense. Property Total Property Services Other Total Three Months Ended September 30, 2015 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 807,978 $ 61,563 $ 124,545 $ 218,763 $ 1,212,849 $ 25,061 $ 1,237,910 Segment operating expenses (1) 187,368 32,629 57,492 78,197 355,686 9,208 364,894 Interest income, TV Azteca, net — — — 2,993 2,993 — 2,993 Segment gross margin 620,610 28,934 67,053 143,559 860,156 15,853 876,009 Segment selling, general, administrative and development expense (1) 31,374 5,824 13,009 14,296 64,503 3,730 68,233 Segment operating profit $ 589,236 $ 23,110 $ 54,044 $ 129,263 $ 795,653 $ 12,123 $ 807,776 Stock-based compensation expense $ 18,345 18,345 Other selling, general, administrative and development expense (2) 28,749 28,749 Depreciation, amortization and accretion 341,096 341,096 Other expense (3) 227,611 227,611 Income from continuing operations before income taxes $ 191,975 Total assets (4) $ 19,353,820 $ 746,355 $ 2,301,888 $ 4,301,308 $ 26,703,371 $ 70,006 $ 153,411 $ 26,926,788 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.5 million and $17.9 million , respectively. (2) Includes $1.6 million of expense previously recorded as segment selling, general, administrative and development expense. (3) Primarily includes interest expense. (4) $12.0 million of assets previously recorded within the Asia, EMEA, and Latin America Property segments have been reclassified to the Other segment. Property Total Property Services Other Total Nine Months Ended September 30, 2016 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 2,518,426 $ 557,734 $ 395,066 $ 720,553 $ 4,191,779 $ 54,340 $ 4,246,119 Segment operating expenses (1) 548,875 315,074 167,908 247,204 1,279,061 21,429 1,300,490 Interest income, TV Azteca, net — — — 8,206 8,206 — 8,206 Segment gross margin 1,969,551 242,660 227,158 481,555 2,920,924 32,911 2,953,835 Segment selling, general, administrative and development expense (1) 107,533 36,376 45,795 45,069 234,773 8,988 243,761 Segment operating profit $ 1,862,018 $ 206,284 $ 181,363 $ 436,486 $ 2,686,151 $ 23,923 $ 2,710,074 Stock-based compensation expense $ 70,212 70,212 Other selling, general, administrative and development expense 93,016 93,016 Depreciation, amortization and accretion 1,137,398 1,137,398 Other expense (2) 577,271 577,271 Income from continuing operations before income taxes $ 832,177 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.9 million and $68.3 million , respectively. (2) Primarily includes interest expense. Property Total Property Services Other Total Nine Months Ended September 30, 2015 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 2,328,699 $ 178,699 $ 270,754 $ 651,112 $ 3,429,264 $ 62,211 $ 3,491,475 Segment operating expenses (1) 502,572 93,917 110,205 221,712 928,406 22,527 950,933 Interest income, TV Azteca, net — — — 8,251 8,251 — 8,251 Segment gross margin 1,826,127 84,782 160,549 437,651 2,509,109 39,684 2,548,793 Segment selling, general, administrative and development expense (1) 89,439 17,133 33,820 44,548 184,940 10,605 195,545 Segment operating profit $ 1,736,688 $ 67,649 $ 126,729 $ 393,103 $ 2,324,169 $ 29,079 $ 2,353,248 Stock-based compensation expense $ 72,251 72,251 Other selling, general, administrative and development expense (2) 88,218 88,218 Depreciation, amortization and accretion 932,972 932,972 Other expense (3) 677,332 677,332 Income from continuing operations before income taxes $ 582,475 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.6 million and $70.7 million , respectively. (2) Includes $3.8 million of expense previously recorded as segment selling, general, administrative and development expense. (3) Primarily includes interest expense and loss on retirement of long-term obligations.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	9 Months Ended
	Sep. 30, 2016
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS On October 21, 2016, the Company entered into a definitive agreement to form a joint venture (“ATC Europe”) with PGGM. The joint venture will focus on pursuing telecommunications real estate investment opportunities in select countries on the continent. At closing, the Company will contribute its German assets into ATC Europe and PGGM will acquire a 49% interest in ATC Europe for a purchase price of 248.2 million Euro ( $270.2 million as of October 21, 2016), subject to various adjustments at closing. The Company will retain operational control and day-to-day oversight of ATC Europe.

DESCRIPTION OF BUSINESS, BASI26

DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	American Tower Corporation (together with its subsidiaries, “ATC” or the “Company”) is one of the largest global real estate investment trusts and a leading independent owner, operator and developer of multitenant communications real estate. The Company’s primary business is the leasing of space on communications sites to wireless service providers, radio and television broadcast companies, wireless data providers, government agencies and municipalities and tenants in a number of other industries, which the Company refers to as its property operations. Additionally, the Company offers tower-related services, referred to as its services operations, in the United States, including site acquisition, zoning and permitting and structural analysis, which primarily support its site leasing business, including the addition of new tenants and equipment on its sites. The Company’s portfolio primarily consists of towers it owns and towers it operates pursuant to long-term lease arrangements, as well as distributed antenna system (“DAS”) networks, which provide seamless coverage solutions for in-building and certain outdoor wireless environments. In addition to the communications sites in its portfolio, the Company manages rooftop and tower sites for property owners under various contractual arrangements. The Company also holds property interests that it leases to communications service providers and third-party tower operators. 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. On April 21, 2016, the Company significantly expanded its Asia segment portfolio by acquiring a 51% controlling ownership interest in Viom Networks Limited (“Viom”), a telecommunications infrastructure company that owns and operates over 42,000 wireless communications towers and 200 indoor DAS networks in India (the “Viom Acquisition”). Subsequent to the closing, Viom was renamed ATC Telecom Infrastructure Private Limited (“ATC TIPL”). The Company operates as a real estate investment trust for U.S. federal income tax purposes (“REIT”). Accordingly, the Company generally is not subject to U.S. federal income taxes on income generated by its REIT operations, including the income derived from leasing space on its towers, as the Company receives a dividends paid deduction for distributions to stockholders that generally offsets its income and gains. However, the Company remains obligated to pay U.S. federal income taxes on earnings from its domestic taxable REIT subsidiaries (“TRSs”). In addition, the Company’s international assets and operations, regardless of their designation for U.S. tax purposes, 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 to be included as part of the REIT. As of September 30, 2016 , the Company’s REIT-qualified businesses included its U.S. tower leasing business, most of its operations in Costa Rica, Germany and Mexico and a majority of its services segment and indoor DAS networks business. The accompanying consolidated and condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission. The financial information included herein is unaudited. However, the Company believes that all adjustments considered necessary for a fair presentation of its financial position and results of operations for such periods have been included herein. The consolidated and condensed consolidated financial statements and related notes should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2015 (the “ 2015 Form 10-K”). The results of operations for the three and nine months ended September 30, 2016 are not necessarily indicative of the results that may be expected for the entire year.
Principles of Consolidation and Basis of Presentation	The accompanying consolidated and condensed consolidated financial statements include the accounts of the Company and those entities in which it has a controlling interest. Investments in entities that the Company does not control are accounted for using the equity or cost method, depending upon the Company’s ability to exercise significant influence over operating and financial policies. All intercompany accounts and transactions have been eliminated.
Accounting Standards Updates	In May 2014, the Financial Accounting Standards Board (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 and will become effective for the Company on January 1, 2018. Early adoption is permitted for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2016. The standard permits the use of either the retrospective or cumulative effect transition method. Leases are not included in the scope of this standard. The Company is evaluating the impact this standard will have on its financial statements. In January 2016, the FASB issued new guidance on the recognition and measurement of financial assets and financial liabilities. The guidance amends certain aspects of recognition, measurement, presentation and disclosure of financial instruments. This standard is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2017. The Company does not expect the adoption of this guidance to have a material effect on its financial statements. In February 2016, the FASB issued new guidance on the accounting for leases. The guidance amends the existing accounting standards for lease accounting, including the requirement that lessees recognize assets and liabilities for leases with terms greater than twelve months in the statement of financial position. Under the new guidance, lessor accounting is largely unchanged. This guidance is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2018. The standard is required to be applied using a modified retrospective approach for all leases existing at, or entered into after, the beginning of the earliest comparative period presented. The Company is evaluating the impact this standard will have on its financial statements. In March 2016, the FASB issued new guidance on the accounting for share-based payment transactions. The guidance amends the accounting for taxes related to stock-based compensation, including how excess tax benefits and a company’s payments for tax withholdings should be classified. This guidance is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2016. The Company early adopted this standard in the second quarter of 2016 and elected to account for forfeitures as they occur, effective January 1, 2016. The adoption of this guidance was not material to the Company’s consolidated financial statements. Additionally, the Company elected to apply the prospective transition method to the amendments related to the presentation of excess tax benefits in the statements of cash flows. In August 2016, the FASB issued new guidance on certain classifications within the statement of cash flows. The guidance addresses, among other things, how cash receipts and cash payments are presented and classified in the statement of cash flows, including payments for costs related to debt prepayments or extinguishment, as well as payments of contingent consideration after an acquisition. The guidance is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption within an interim period. The Company is evaluating the impact this standard will have on its financial statements.

PREPAID AND OTHER CURRENT ASS27

PREPAID AND OTHER CURRENT ASSETS (Tables)	9 Months Ended
	Sep. 30, 2016
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid and other current assets	Prepaid and other current assets consisted of the following (in thousands): As of September 30, 2016 December 31, 2015 Prepaid operating ground leases $ 129,515 $ 128,542 Prepaid income tax 109,949 45,056 Unbilled receivables 59,928 34,173 Prepaid assets 54,584 32,892 Value added tax and other consumption tax receivables 24,519 30,239 Other miscellaneous current assets 37,341 35,333 Total $ 415,836 $ 306,235

GOODWILL AND OTHER INTANGIBLE28

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	9 Months Ended
	Sep. 30, 2016
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 were as follows (in thousands): Property Services Total U.S. Asia (1) EMEA Latin America Balance as of January 1, 2016 $ 3,379,163 $ 170,719 $ 132,570 $ 407,365 $ 1,988 $ 4,091,805 Additions (2) — 826,735 42,297 5,008 — 874,040 Effect of foreign currency translation — (2,890 ) (19,703 ) 53,972 — 31,379 Balance as of September 30, 2016 $ 3,379,163 $ 994,564 $ 155,164 $ 466,345 $ 1,988 $ 4,997,224 _______________ (1) Includes approximately $826.7 million of goodwill assumed in the Viom Acquisition (see note 13). (2) Balances have been revised to reflect purchase accounting measurement period adjustments.
Finite intangible assets	The Company’s other intangible assets subject to amortization consisted of the following: As of September 30, 2016 As of December 31, 2015 Estimated Useful Lives Gross Carrying Value Accumulated Amortization Net Book Value Gross Carrying Value Accumulated Amortization Net Book Value (years) (in thousands) Acquired network location intangibles (1) Up to 20 $ 4,626,477 $ (1,229,177 ) $ 3,397,300 $ 3,980,281 $ (1,052,393 ) $ 2,927,888 Acquired customer-related intangibles 15-20 10,242,624 (2,115,242 ) 8,127,382 8,640,554 (1,763,853 ) 6,876,701 Acquired licenses and other intangibles 3-20 28,332 (4,283 ) 24,049 28,293 (5,486 ) 22,807 Economic Rights, TV Azteca 70 19,376 (10,143 ) 9,233 21,688 (11,208 ) 10,480 Total other intangible assets $ 14,916,809 $ (3,358,845 ) $ 11,557,964 $ 12,670,816 $ (2,832,940 ) $ 9,837,876 _______________ (1) 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.
Expected future amortization expenses	Based on current exchange rates, the Company expects to record amortization expense as follows over the remaining current year and the five subsequent years (in millions): Fiscal Year Remainder of 2016 $ 179.6 2017 716.2 2018 714.0 2019 711.1 2020 692.3 2021 682.8

ACCRUED EXPENSES (Tables)

ACCRUED EXPENSES (Tables)	9 Months Ended
	Sep. 30, 2016
Accrued Liabilities, Current [Abstract]
Schedule of accrued expenses	Accrued expenses consisted of the following (in thousands): As of September 30, 2016 December 31, 2015 Accrued property and real estate taxes $ 114,839 $ 75,827 Payroll and related withholdings 63,848 62,334 Accrued rent 52,926 54,732 Accrued construction costs 19,517 19,857 Accrued income tax payable 2,480 11,704 Other accrued expenses 318,379 291,959 Total $ 571,989 $ 516,413

LONG-TERM OBLIGATIONS (Tables)

LONG-TERM OBLIGATIONS (Tables)	9 Months Ended
	Sep. 30, 2016
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term financing arrangements	Viom indebtedness— Amounts outstanding and key terms of the Viom indebtedness consisted of the following as of September 30, 2016 (in millions, except percentages): Amount Outstanding (INR) Amount Outstanding (USD) Interest Rate (Range) Maturity Date (Range) Term loans 33,533 $ 503.4 10.50% - 11.20% March 31, 2017 - November 30, 2024 Debenture 6,000 $ 90.1 9.90 % April 28, 2020 Working capital facilities — — 9.85% - 11.80% October 23, 2016 - March 18, 2017 Outstanding amounts under the Company’s long-term obligations, reflecting discounts, premiums and debt issuance costs, consisted of the following (in thousands): As of September 30, 2016 December 31, 2015 Maturity Date Series 2013-1A securities (1) $ 498,351 $ 497,478 March 15, 2018 Series 2013-2A securities (2) 1,289,872 1,288,689 March 15, 2023 Series 2015-1 notes (3) 346,897 346,262 June 15, 2020 Series 2015-2 notes (4) 519,271 518,776 June 16, 2025 2012 GTP notes (5) 180,846 281,902 March 15, 2019 Unison notes (6) 200,616 201,930 Various Viom indebtedness (7) 593,491 — Various Viom preference shares (8) 25,021 — Various Shareholder loans (9) 151,723 145,540 Various BR Towers debentures (10) 103,194 85,219 October 15, 2023 Colombian credit facility (11) 60,131 59,640 April 24, 2021 South African facility (12) 50,911 53,175 December 17, 2020 Brazil credit facility (13) 38,900 21,868 January 15, 2022 Indian working capital facility (14) 662 8,752 October 31, 2016 Total American Tower subsidiary debt 4,059,886 3,509,231 2013 Credit Facility 137,692 1,225,000 June 28, 2019 Term Loan 994,553 1,993,601 January 29, 2021 2014 Credit Facility 1,840,000 1,980,000 January 29, 2021 4.500% senior notes 998,357 997,693 January 15, 2018 3.40% senior notes 999,661 999,769 February 15, 2019 7.25% senior notes 296,665 296,242 May 15, 2019 2.800% senior notes 744,557 743,557 June 1, 2020 5.050% senior notes 697,165 697,216 September 1, 2020 3.300% senior notes 744,465 — February 15, 2021 3.450% senior notes 643,529 642,786 September 15, 2021 5.900% senior notes 497,203 497,188 November 1, 2021 2.250% senior notes 594,903 — January 15, 2022 4.70% senior notes 695,821 695,374 March 15, 2022 3.50% senior notes 988,820 987,966 January 31, 2023 5.00% senior notes 1,002,816 1,003,453 February 15, 2024 4.000% senior notes 739,717 739,057 June 1, 2025 4.400% senior notes 495,102 — February 15, 2026 3.375% senior notes 983,007 — October 15, 2026 3.125% senior notes 396,702 — January 15, 2027 Total American Tower Corporation debt 14,490,735 13,498,902 Other debt, including capital lease obligations 128,515 110,876 Total 18,679,136 17,119,009 Less current portion of long-term obligations (242,992 ) (50,202 ) Long-term obligations $ 18,436,144 $ 17,068,807 _______________ (1) Maturity date represents anticipated repayment date; final legal maturity is March 15, 2043. (2) Maturity date represents anticipated repayment date; final legal maturity is March 15, 2048. (3) Maturity date represents anticipated repayment date; final legal maturity is June 15, 2045. (4) Maturity date represents anticipated repayment date; final legal maturity is June 15, 2050. (5) Secured debt assumed by the Company in connection with its acquisition of MIP Tower Holdings LLC. Maturity date represents anticipated repayment date; final legal maturity is March 15, 2042. During the nine months ended September 30, 2016 , the Company repaid the $94.1 million outstanding under the Secured Tower Cellular Site Revenue Notes, Series 2012-1 Class A and released 472 sites in connection with this repayment. (6) Secured debt assumed by the Company in connection with its acquisition of certain legal entities from Unison Holdings LLC and Unison Site Management II, L.L.C (together, “Unison”). In October 2016, the Company repaid the $67.0 million outstanding under the Secured Cellular Site Revenue Notes, Series 2010-1, Class C. The anticipated repayment date for the remaining series is April 15, 2020; final legal maturity date is April 15, 2040. (7) Debt primarily assumed by the Company in connection with the Viom Acquisition. Maturity dates begin March 31, 2017. Denominated in Indian Rupees (“INR”). In October 2016, ATC TIPL refinanced 3.6 billion INR ( $53.5 million as of September 30, 2016) of Viom assumed indebtedness with borrowings under a new short-term committed loan facility with a borrowing capacity of 5.8 billion INR ( $87.1 million as of September 30, 2016) and repaid an additional 1.4 billion INR ( $21.0 million as of September 30, 2016) of Viom assumed indebtedness with cash on hand. (8) Mandatorily redeemable preference shares (the “Preference Shares”) classified as debt, assumed by the Company in connection with the Viom Acquisition. The shares are to be redeemed in equal parts on March 26, 2017 and March 26, 2018. (9) Reflects balances owed to the Company’s joint venture partners in Ghana and Uganda. The Ghana loan is denominated in Ghanaian Cedi and the Uganda loan is denominated in U.S. Dollars. (10) Publicly issued debentures assumed by the Company in connection with its acquisition of BR Towers S.A. Denominated in Brazilian Reais (“BRL”). (11) Denominated in Colombian Pesos and amortizes through April 24, 2021. (12) Denominated in South African Rand and amortizes through December 17, 2020. (13) Denominated in BRL. (14) Denominated in INR. This agreement provides that the maturity date may be extended for additional 30-day periods.
Schedule of line of credit facilities	As of September 30, 2016 , the key terms under the 2013 Credit Facility, the 2014 Credit Facility and the Term Loan were as follows: Outstanding Principal Balance (in millions) Undrawn letters of credit (in millions) Maturity Date Current margin over LIBOR (1) Current commitment fee (2) 2013 Credit Facility $ 137.7 $ 3.2 June 28, 2019 (3) 1.250 % 0.150 % 2014 Credit Facility $ 1,840.0 $ 7.4 January 29, 2021 (3) 1.250 % 0.150 % Term Loan $ 1,000.0 $ — January 29, 2021 1.250 % N/A _______________ (1) LIBOR means the London Interbank Offered Rate. (2) Fee on undrawn portion of each credit facility. (3) Subject to two optional renewal periods.

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Schedule of fair value	The fair values of the Company’s financial assets and liabilities that are required to be measured on a recurring basis at fair value were as follows (in thousands): September 30, 2016 December 31, 2015 Fair Value Measurements Using Fair Value Measurements Using Level 2 Level 3 Level 2 Level 3 Assets: Interest rate swap agreements $ 212 — $ 692 — Embedded derivative in lease agreement — $ 13,513 — $ 14,176 Liabilities: Acquisition-related contingent consideration — $ 21,575 — $ 12,436

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	9 Months Ended
	Sep. 30, 2016
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Summary of stock-based compensation expenses	During the three and nine months ended September 30, 2016 and 2015 , the Company recorded and capitalized the following stock-based compensation expenses (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Stock-based compensation expense $ 20,226 $ 18,345 $ 70,212 $ 72,251 Stock-based compensation expense capitalized as property and equipment $ 353 $ 495 $ 1,115 $ 1,554
Assumptions used to determine the grant date fair value for options granted	Key assumptions used to apply this pricing model during the nine months ended September 30, 2016 were as follows: Range of risk-free interest rate 1.00% - 1.73% Weighted average risk-free interest rate 1.45% Range of expected life of stock options 4.5 - 5.2 years Range of expected volatility of the underlying stock price 20.64% - 21.45% Weighted average expected volatility of underlying stock price 21.45% Range of expected annual dividend yield 1.85% - 2.40%
Summary of the company's option activity	The Company’s option activity for the nine months ended September 30, 2016 was as follows: Number of Options Outstanding as of January 1, 2016 7,680,819 Granted 1,140,366 Exercised (1,263,309 ) Forfeited (16,320 ) Expired (800 ) Outstanding as of September 30, 2016 7,540,756
Summary of the company's restricted stock unit activity	The Company’s RSU and PSU activity for the nine months ended September 30, 2016 was as follows: RSUs PSUs Outstanding as of January 1, 2016 (1) 1,656,993 33,377 Granted (2) 774,739 192,719 Vested (641,810 ) — Forfeited (84,461 ) — Outstanding as of September 30, 2016 1,705,461 226,096 _______________ (1) PSUs represent the shares issuable for the 2015 PSUs at the end of the three -year performance cycle based on exceeding the performance metric for the first year’s performance period. (2) PSUs represent the target number of shares issuable at the end of the three -year performance cycle attributable to the second year’s performance period for the 2015 PSUs and the target number of shares issuable at the end of the three -year performance cycle for the 2016 PSUs.

REDEEMABLE NONCONTROLLING INT33

REDEEMABLE NONCONTROLLING INTERESTS (Tables)	9 Months Ended
	Sep. 30, 2016
Noncontrolling Interest [Abstract]
Reconciliation of the changes in the redeemable noncontrolling items	The following is a reconciliation of the changes in the Redeemable noncontrolling interests (in thousands): Balance as of January 1, 2016 $ — Fair value at acquisition 1,100,804 Net income attributable to noncontrolling interests 1,536 Foreign currency translation adjustment attributable to noncontrolling interests (2,138 ) Balance as of September 30, 2016 $ 1,100,202

EQUITY (Tables)

EQUITY (Tables)	9 Months Ended
	Sep. 30, 2016
Stockholders' Equity Attributable to Parent [Abstract]
Schedule of declared or paid cash distributions	During the nine months ended September 30, 2016 , the Company declared or paid the following cash distributions: Declaration Date Payment Date Record Date Distribution per share Aggregate Payment Amount (in millions) Common Stock December 3, 2015 January 13, 2016 December 16, 2015 $ 0.49 $ 207.7 March 9, 2016 April 28, 2016 April 12, 2016 $ 0.51 $ 216.5 June 2, 2016 July 15, 2016 June 17, 2016 $ 0.53 $ 225.4 September 16, 2016 October 17, 2016 September 30, 2016 $ 0.55 $ 234.1 Series A Preferred Stock January 14, 2016 February 16, 2016 February 1, 2016 $ 1.3125 $ 7.9 April 16, 2016 May 16, 2016 May 1, 2016 $ 1.3125 $ 7.9 July 22, 2016 August 15, 2016 August 1, 2016 $ 1.3125 $ 7.9 Series B Preferred Stock January 14, 2016 February 16, 2016 February 1, 2016 $ 13.75 $ 18.9 April 16, 2016 May 16, 2016 May 1, 2016 $ 13.75 $ 18.9 July 22, 2016 August 15, 2016 August 1, 2016 $ 13.75 $ 18.9

EARNINGS PER COMMON SHARE (Tabl

EARNINGS PER COMMON SHARE (Tables)	9 Months Ended
	Sep. 30, 2016
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 (in thousands, except per share data): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Net income attributable to American Tower Corporation stockholders $ 264,509 $ 102,999 $ 727,218 $ 452,372 Dividends on preferred stock (26,781 ) (26,781 ) (80,344 ) (63,382 ) Net income attributable to American Tower Corporation common stockholders 237,728 76,218 646,874 388,990 Basic weighted average common shares outstanding 425,517 423,375 424,831 417,280 Dilutive securities 4,408 3,852 4,188 4,072 Diluted weighted average common shares outstanding 429,925 427,227 429,019 421,352 Basic net income attributable to American Tower Corporation common stockholders per common share $ 0.56 $ 0.18 $ 1.52 $ 0.93 Diluted net income attributable to American Tower Corporation common stockholders per common share $ 0.55 $ 0.18 $ 1.51 $ 0.92
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 because the effect would be anti-dilutive (in thousands, on a weighted average basis): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Restricted stock awards — — 2 — Stock options 8 1,996 1,619 1,472 Preferred stock 17,473 17,368 17,473 14,724

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Future minimum rental receipts under operating lease agreements	Future minimum rental receipts expected from tenants under non-cancellable operating lease agreements in effect at September 30, 2016 were as follows (in millions): Remainder of 2016 $ 1,271 2017 4,710 2018 4,543 2019 4,269 2020 3,916 Thereafter 13,825 Total $ 32,534
Future minimum rental payments under non-cancelable operating 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 September 30, 2016 are as follows (in millions): Remainder of 2016 $ 244 2017 912 2018 886 2019 854 2020 815 Thereafter 7,370 Total $ 11,081

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Schedule of merger and acquisition related costs	During the three and nine months ended September 30, 2016 and 2015 , the Company recorded acquisition and merger related expenses and integration costs as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Acquisition and merger related expenses $ 1,124 $ 8,587 $ 7,844 $ 16,574 Integration costs $ 1,846 $ 5,938 $ 8,351 $ 12,218
Schedule of recognized identified assets acquired and liabilities assumed	The following table summarizes the preliminary and updated allocations of the purchase prices paid and the amounts of assets acquired and liabilities assumed for the fiscal year 2015 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Preliminary Allocation Updated Allocation Latin America Other Latin America Other TIM TIM (1) Current assets $ — $ 1,113 $ — $ 1,113 Non-current assets — 995 — 995 Property and equipment 275,630 42,716 274,530 42,716 Intangible assets (2): Customer-related intangible assets 361,822 63,001 361,765 62,832 Network location intangible assets 115,562 37,691 115,795 37,691 Current liabilities (3,192 ) (624 ) (3,192 ) (624 ) Deferred tax liability — — — — Other non-current liabilities (74,966 ) (4,028 ) (74,966 ) (4,028 ) Net assets acquired 674,856 140,864 673,932 140,695 Goodwill 122,011 24,011 122,116 24,011 Fair value of net assets acquired 796,867 164,875 796,048 164,706 Debt assumed — — — — Purchase Price $ 796,867 $ 164,875 $ 796,048 $ 164,706 _______________ (1) The allocation of the purchase price related to the 5,301 communications sites acquired from TIM on April 29, 2015 and September 30, 2015 was finalized during the nine months ended September 30, 2016. (2) Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years . The following table summarizes the preliminary allocation of the purchase price for the fiscal year 2016 acquisitions based upon their estimated fair value at the date of acquisition (in thousands). Balances are reflected in the accompanying consolidated balance sheet as of September 30, 2016 . Asia Other Viom Current assets $ 281,888 $ 12,619 Non-current assets 37,737 145 Property and equipment 707,560 46,026 Intangible assets (1): Customer-related intangible assets 1,435,164 86,779 Network location intangible assets 691,484 21,258 Current liabilities (181,101 ) (7,701 ) Deferred tax liability (657,810 ) (14,290 ) Other non-current liabilities (105,458 ) (6,477 ) Net assets acquired 2,209,464 138,359 Goodwill (2) 826,735 47,200 Fair value of net assets acquired 3,036,199 185,559 Debt assumed (786,889 ) — Redeemable noncontrolling interests (1,100,804 ) — Purchase Price $ 1,148,506 $ 185,559 _______________ (1) Customer-related intangible assets and network location intangible assets are amortized on a straight-line basis over periods of up to 20 years . (2) Primarily results from purchase accounting adjustments, which are not deductible for tax purposes in any foreign jurisdiction.
Schedule of pro forma information	The following table presents the unaudited pro forma financial results as if the 2016 acquisitions had occurred on January 1, 2015 and acquisitions completed in 2015 had occurred on January 1, 2014. The pro forma results do not include any anticipated cost synergies, costs or other integration impacts. Accordingly, such pro forma amounts are not necessarily indicative of the results that actually would have occurred had the transactions been completed on the date indicated, nor are they indicative of the future operating results of the Company. Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Pro forma revenues $ 1,517,197 $ 1,449,460 $ 4,498,458 $ 4,372,304 Pro forma net income attributable to American Tower Corporation common stockholders $ 238,364 $ 72,885 $ 643,780 $ 346,097 Pro forma net income per common share amounts: Basic net income attributable to American Tower Corporation common stockholders $ 0.56 $ 0.17 $ 1.52 $ 0.82 Diluted net income attributable to American Tower Corporation common stockholders $ 0.55 $ 0.17 $ 1.50 $ 0.81

BUSINESS SEGMENTS (Tables)

BUSINESS SEGMENTS (Tables)	9 Months Ended
	Sep. 30, 2016
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 three and nine months ended September 30, 2016 and 2015 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, as the amounts are not utilized in assessing each segment’s performance. Property Total Property Services Other Total Three Months Ended September 30, 2016 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 837,002 $ 269,907 $ 130,664 $ 260,363 $ 1,497,936 $ 16,909 $ 1,514,845 Segment operating expenses (1) 188,777 154,139 53,787 88,396 485,099 5,540 490,639 Interest income, TV Azteca, net — — — 2,742 2,742 — 2,742 Segment gross margin 648,225 115,768 76,877 174,709 1,015,579 11,369 1,026,948 Segment selling, general, administrative and development expense (1) 35,526 15,030 12,958 15,454 78,968 2,726 81,694 Segment operating profit $ 612,699 $ 100,738 $ 63,919 $ 159,255 $ 936,611 $ 8,643 $ 945,254 Stock-based compensation expense $ 20,226 20,226 Other selling, general, administrative and development expense 30,215 30,215 Depreciation, amortization and accretion 397,999 397,999 Other expense (2) 211,042 211,042 Income from continuing operations before income taxes $ 285,772 Total assets $ 18,837,629 $ 4,612,766 $ 2,120,592 $ 4,885,066 $ 30,456,053 $ 60,810 $ 138,664 $ 30,655,527 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.6 million and $19.6 million , respectively. (2) Primarily includes interest expense. Property Total Property Services Other Total Three Months Ended September 30, 2015 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 807,978 $ 61,563 $ 124,545 $ 218,763 $ 1,212,849 $ 25,061 $ 1,237,910 Segment operating expenses (1) 187,368 32,629 57,492 78,197 355,686 9,208 364,894 Interest income, TV Azteca, net — — — 2,993 2,993 — 2,993 Segment gross margin 620,610 28,934 67,053 143,559 860,156 15,853 876,009 Segment selling, general, administrative and development expense (1) 31,374 5,824 13,009 14,296 64,503 3,730 68,233 Segment operating profit $ 589,236 $ 23,110 $ 54,044 $ 129,263 $ 795,653 $ 12,123 $ 807,776 Stock-based compensation expense $ 18,345 18,345 Other selling, general, administrative and development expense (2) 28,749 28,749 Depreciation, amortization and accretion 341,096 341,096 Other expense (3) 227,611 227,611 Income from continuing operations before income taxes $ 191,975 Total assets (4) $ 19,353,820 $ 746,355 $ 2,301,888 $ 4,301,308 $ 26,703,371 $ 70,006 $ 153,411 $ 26,926,788 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $0.5 million and $17.9 million , respectively. (2) Includes $1.6 million of expense previously recorded as segment selling, general, administrative and development expense. (3) Primarily includes interest expense. (4) $12.0 million of assets previously recorded within the Asia, EMEA, and Latin America Property segments have been reclassified to the Other segment. Property Total Property Services Other Total Nine Months Ended September 30, 2016 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 2,518,426 $ 557,734 $ 395,066 $ 720,553 $ 4,191,779 $ 54,340 $ 4,246,119 Segment operating expenses (1) 548,875 315,074 167,908 247,204 1,279,061 21,429 1,300,490 Interest income, TV Azteca, net — — — 8,206 8,206 — 8,206 Segment gross margin 1,969,551 242,660 227,158 481,555 2,920,924 32,911 2,953,835 Segment selling, general, administrative and development expense (1) 107,533 36,376 45,795 45,069 234,773 8,988 243,761 Segment operating profit $ 1,862,018 $ 206,284 $ 181,363 $ 436,486 $ 2,686,151 $ 23,923 $ 2,710,074 Stock-based compensation expense $ 70,212 70,212 Other selling, general, administrative and development expense 93,016 93,016 Depreciation, amortization and accretion 1,137,398 1,137,398 Other expense (2) 577,271 577,271 Income from continuing operations before income taxes $ 832,177 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.9 million and $68.3 million , respectively. (2) Primarily includes interest expense. Property Total Property Services Other Total Nine Months Ended September 30, 2015 U.S. Asia EMEA Latin America (in thousands) Segment revenues $ 2,328,699 $ 178,699 $ 270,754 $ 651,112 $ 3,429,264 $ 62,211 $ 3,491,475 Segment operating expenses (1) 502,572 93,917 110,205 221,712 928,406 22,527 950,933 Interest income, TV Azteca, net — — — 8,251 8,251 — 8,251 Segment gross margin 1,826,127 84,782 160,549 437,651 2,509,109 39,684 2,548,793 Segment selling, general, administrative and development expense (1) 89,439 17,133 33,820 44,548 184,940 10,605 195,545 Segment operating profit $ 1,736,688 $ 67,649 $ 126,729 $ 393,103 $ 2,324,169 $ 29,079 $ 2,353,248 Stock-based compensation expense $ 72,251 72,251 Other selling, general, administrative and development expense (2) 88,218 88,218 Depreciation, amortization and accretion 932,972 932,972 Other expense (3) 677,332 677,332 Income from continuing operations before income taxes $ 582,475 _______________ (1) Segment operating expenses and segment selling, general, administrative and development expenses exclude stock-based compensation expense of $1.6 million and $70.7 million , respectively. (2) Includes $3.8 million of expense previously recorded as segment selling, general, administrative and development expense. (3) Primarily includes interest expense and loss on retirement of long-term obligations.

DESCRIPTION OF BUSINESS, BASI39

DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) site in Thousands	9 Months Ended
	Sep. 30, 2016joint_venture	Apr. 21, 2016sitesystem
Concentration Risk [Line Items]
Number of joint ventures the Company has a controlling interest in (in joint ventures) | joint_venture	2
Joint Venture, Ghana And Uganda
Concentration Risk [Line Items]
Ownership interest (as a percent)	51.00%
Noncontrolling interest, ownership percentage by noncontrolling owners (as a percent)	49.00%
Joint Venture, South Africa
Concentration Risk [Line Items]
Ownership interest (as a percent)	75.00%
Noncontrolling interest, ownership percentage by noncontrolling owners (as a percent)	25.00%
ATC, TIPL
Concentration Risk [Line Items]
Ownership interest (as a percent)	51.00%
Viom Transaction
Concentration Risk [Line Items]
Percentage of voting interest acquired (as a percent)		51.00%
Number of communications sites acquired (in number of towers) | site		42
Distributed antenna systems acquired (systems) | system		200

PREPAID AND OTHER CURRENT ASS40

PREPAID AND OTHER CURRENT ASSETS (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid operating ground leases	$ 129,515	$ 128,542
Prepaid income tax	109,949	45,056
Unbilled receivables	59,928	34,173
Prepaid assets	54,584	32,892
Value added tax and other consumption tax receivables	24,519	30,239
Other miscellaneous current assets	37,341	35,333
Total	$ 415,836	$ 306,235

GOODWILL AND OTHER INTANGIBLE41

GOODWILL AND OTHER INTANGIBLE ASSETS - CHANGES IN THE CARRYING VALUE OF GOODWILL (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 4,091,805
Additions	874,040
Effect of foreign currency translation	31,379
Goodwill, ending balance	4,997,224
Viom Transaction
Goodwill [Roll Forward]
Goodwill, ending balance	826,700
Services
Goodwill [Roll Forward]
Goodwill, beginning balance	1,988
Additions	0
Effect of foreign currency translation	0
Goodwill, ending balance	1,988
United States | Property
Goodwill [Roll Forward]
Goodwill, beginning balance	3,379,163
Additions	0
Effect of foreign currency translation	0
Goodwill, ending balance	3,379,163
Asia | Property
Goodwill [Roll Forward]
Goodwill, beginning balance	170,719
Additions	826,735
Effect of foreign currency translation	(2,890)
Goodwill, ending balance	994,564
EMEA | Property
Goodwill [Roll Forward]
Goodwill, beginning balance	132,570
Additions	42,297
Effect of foreign currency translation	(19,703)
Goodwill, ending balance	155,164
Latin America | Property
Goodwill [Roll Forward]
Goodwill, beginning balance	407,365
Additions	5,008
Effect of foreign currency translation	53,972
Goodwill, ending balance	$ 466,345

GOODWILL AND OTHER INTANGIBLE42

GOODWILL AND OTHER INTANGIBLE ASSETS - SUMMARY OF INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 14,916,809	$ 12,670,816
Accumulated Amortization	(3,358,845)	(2,832,940)
Net Book Value	11,557,964	9,837,876
Acquired Network Location
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	4,626,477	3,980,281
Accumulated Amortization	(1,229,177)	(1,052,393)
Net Book Value	$ 3,397,300	$ 2,927,888
Acquired Network Location | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)	0 years
Acquired Network Location | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)	20 years	20 years
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 10,242,624	$ 8,640,554
Accumulated Amortization	(2,115,242)	(1,763,853)
Net Book Value	$ 8,127,382	$ 6,876,701
Finite-lived intangible asset, useful life (in years)	20 years	20 years
Customer Relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)	15 years
Customer Relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)	20 years
Acquired Licenses And Other Intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 28,332	$ 28,293
Accumulated Amortization	(4,283)	(5,486)
Net Book Value	$ 24,049	22,807
Acquired Licenses And Other Intangibles | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)	3 years
Acquired Licenses And Other Intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)	20 years
Economic Rights, TV Azteca
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 19,376	21,688
Accumulated Amortization	(10,143)	(11,208)
Net Book Value	$ 9,233	$ 10,480
Finite-lived intangible asset, useful life (in years)	70 years

GOODWILL AND OTHER INTANGIBLE43

GOODWILL AND OTHER INTANGIBLE ASSETS - EXPECTED FUTURE AMORTIZATION EXPENSE (Details) $ in Millions	Sep. 30, 2016USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2016	$ 179.6
2,017	716.2
2,018	714
2,019	711.1
2,020	692.3
2,021	$ 682.8

GOODWILL AND OTHER INTANGIBLE44

GOODWILL AND OTHER INTANGIBLE ASSETS - NARRATIVE (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 183.9	$ 154.4	$ 521	$ 412.5
Weighted Average
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, remaining amortization period			16 years

ACCRUED EXPENSES (Details)

ACCRUED EXPENSES (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accrued Liabilities, Current [Abstract]
Accrued property and real estate taxes	$ 114,839	$ 75,827
Payroll and related withholdings	63,848	62,334
Accrued rent	52,926	54,732
Accrued construction costs	19,517	19,857
Accrued income tax payable	2,480	11,704
Other accrued expenses	318,379	291,959
Total	$ 571,989	$ 516,413

LONG-TERM OBLIGATIONS - LONG-TE

LONG-TERM OBLIGATIONS - LONG-TERM FINANCING ARRANGEMENTS (Details) $ in Thousands, ₨ in Billions	1 Months Ended		9 Months Ended
	Oct. 28, 2016USD ($)	Oct. 28, 2016INR (₨)	Sep. 30, 2016USD ($)site	May 13, 2016	Jan. 12, 2016	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Other debt, including capital lease obligations			$ 128,515			$ 110,876
Debt, long-term and short-term, combined amount			18,679,136			17,119,009
Less current portion long-term obligations			(242,992)			(50,202)
Long-term debt, excluding current maturities			18,436,144			17,068,807
Subsidiaries
Debt Instrument [Line Items]
Long-term debt			4,059,886			3,509,231
Parent
Debt Instrument [Line Items]
Long-term debt			14,490,735			13,498,902
Series 2012-1 Class A Notes [Member] | Secured Debt
Debt Instrument [Line Items]
Repayments of secured debt			94,100
Commercial Mortgage Pass Through Certificates Series 2013 | Secured Debt | Secured Tower Revenue Securities, Series 2013-1A
Debt Instrument [Line Items]
Long-term debt			498,351			497,478
Commercial Mortgage Pass Through Certificates Series 2013 | Secured Debt | Secured Tower Revenue Securities, Series 2013-2A
Debt Instrument [Line Items]
Long-term debt			1,289,872			1,288,689
Series 2015-1 Class A | Secured Debt
Debt Instrument [Line Items]
Long-term debt			346,897			346,262
Series 2015-2 Class A | Secured Debt
Debt Instrument [Line Items]
Long-term debt			$ 519,271			518,776
GTP Notes
Debt Instrument [Line Items]
Number of sites released upon repayment (in sites) | site			472
GTP Notes | Secured Debt
Debt Instrument [Line Items]
Long-term debt			$ 180,846			281,902
Secured Cellular Site Revenue Notes | Secured Debt
Debt Instrument [Line Items]
Long-term debt			200,616			201,930
Viom Debt | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt			593,491			0
Less current portion long-term obligations			(53,500)
Short-term committed loan facility borrowing capacity			87,100
Repayments of outstanding debt			21,000
Viom Debt | Unsecured Debt | Subsequent Event
Debt Instrument [Line Items]
Less current portion long-term obligations | ₨		₨ (3.6)
Short-term committed loan facility borrowing capacity | ₨		5.8
Repayments of outstanding debt | ₨		₨ 1.4
Viom preferred shares | Mandatorily Redeemable Preferred Stock
Debt Instrument [Line Items]
Long-term debt			25,021			0
Shareholder Loans | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt			151,723			145,540
BR Towers Debentures | Secured Debt
Debt Instrument [Line Items]
Long-term debt			103,194			85,219
Colombian Long Term Credit Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			60,131			59,640
South African Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			50,911			53,175
Brazil Credit Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			38,900			21,868
Indian Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			662			8,752
Credit Facility 2013 | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			137,692			1,225,000
Term Loan 2013 | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt			994,553			1,993,601
Credit Facility 2014 | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			1,840,000			1,980,000
4.50% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 998,357			$ 997,693
Long-term debt, stated interest rate (as a percent)			4.50%			4.50%
3.40% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 999,661			$ 999,769
Long-term debt, stated interest rate (as a percent)			3.40%			3.40%
7.25% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 296,665			$ 296,242
Long-term debt, stated interest rate (as a percent)			7.25%			7.25%
2.80% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 744,557			$ 743,557
Long-term debt, stated interest rate (as a percent)			2.80%			2.80%
5.05% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 697,165			$ 697,216
Long-term debt, stated interest rate (as a percent)			5.05%			5.05%
3.30% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 744,465			$ 0
Long-term debt, stated interest rate (as a percent)			3.30%		3.30%	3.30%
3.450% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 643,529			$ 642,786
Long-term debt, stated interest rate (as a percent)			3.45%			3.45%
5.90% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 497,203			$ 497,188
Long-term debt, stated interest rate (as a percent)			5.90%			5.90%
2.250% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 594,903			$ 0
Long-term debt, stated interest rate (as a percent)			2.25%			2.25%
4.70% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 695,821			$ 695,374
Long-term debt, stated interest rate (as a percent)			4.70%			4.70%
3.50% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 988,820			$ 987,966
Long-term debt, stated interest rate (as a percent)			3.50%			3.50%
5.00% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 1,002,816			$ 1,003,453
Long-term debt, stated interest rate (as a percent)			5.00%			5.00%
4.00% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 739,717			$ 739,057
Long-term debt, stated interest rate (as a percent)			4.00%			4.00%
4.40% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 495,102			$ 0
Long-term debt, stated interest rate (as a percent)			4.40%		4.40%	4.40%
3.375% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 983,007			$ 0
Long-term debt, stated interest rate (as a percent)			3.375%	3.375%		3.375%
3.125% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt			$ 396,702			$ 0
Long-term debt, stated interest rate (as a percent)			3.125%			3.125%
Series 2010-1 Class C | Secured Debt
Debt Instrument [Line Items]
Less current portion long-term obligations			$ (67,400)
Series 2010-1 Class C | Secured Debt | Subsequent Event
Debt Instrument [Line Items]
Repayments of senior debt	$ 67,000

LONG-TERM OBLIGATIONS - SCHEDUL

LONG-TERM OBLIGATIONS - SCHEDULE OF LINES OF CREDIT (Details) $ in Thousands, ₨ in Millions	9 Months Ended
	Sep. 30, 2016USD ($)	Sep. 30, 2016INR (₨)	Dec. 31, 2015USD ($)
Viom Term Loan | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt	$ 503,400	₨ 33,533
Viom Debenture | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt	$ 90,100	₨ 6,000
Long-term debt, stated interest rate (as a percent)	9.90%	9.90%
Viom Working Capital Facilities | Line of Credit
Line of Credit Facility [Line Items]
Line of credit	$ 0	₨ 0
Credit Facility 2013 | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit	137,692		$ 1,225,000
Principal amount	137,700
Undrawn letters of credit	$ 3,200
Commitment fee (as a percent)	0.15%
Credit Facility 2013 | Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.25%
Credit Facility 2014 | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit	$ 1,840,000		1,980,000
Principal amount	1,840,000
Undrawn letters of credit	$ 7,400
Commitment fee (as a percent)	0.15%
Credit Facility 2014 | Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.25%
Term Loan 2013 | Unsecured Debt
Line of Credit Facility [Line Items]
Long-term debt	$ 994,553		$ 1,993,601
Principal amount	1,000,000
Undrawn letters of credit	$ 0
Term Loan 2013 | Unsecured Debt | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.25%
Minimum | Viom Term Loan | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, stated interest rate (as a percent)	10.50%	10.50%
Minimum | Viom Working Capital Facilities | Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt, stated interest rate (as a percent)	9.85%	9.85%
Maximum | Viom Term Loan | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, stated interest rate (as a percent)	11.20%	11.20%
Maximum | Viom Working Capital Facilities | Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt, stated interest rate (as a percent)	11.80%	11.80%

LONG-TERM OBLIGATIONS - NARRATI

LONG-TERM OBLIGATIONS - NARRATIVE (Details) ₨ / shares in Units, $ in Thousands, ₨ in Millions	Oct. 17, 2016USD ($)	Sep. 30, 2016USD ($)shares	May 13, 2016USD ($)	Jan. 12, 2016USD ($)	Oct. 28, 2016INR (₨)	Sep. 30, 2016USD ($)installmentshares	Sep. 30, 2015USD ($)	Sep. 30, 2016INR (₨)₨ / sharesshares	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Current portion of long-term obligations		$ 242,992				$ 242,992			$ 50,202
Proceeds from issuance of senior notes, net						3,236,383	$ 1,492,298
Borrowings under credit facilities						1,529,477	$ 5,727,831
Credit Facility 2013 | Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount		137,700				137,700
Borrowings under credit facilities						1,400,000
Repayment of indebtedness under credit facility						2,500,000
Credit Facility 2014 | Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount		1,840,000				1,840,000
Borrowings under credit facilities						80,000
Repayment of indebtedness under credit facility						220,000
Credit Facility 2014 | Revolving Credit Facility | Subsequent Event
Debt Instrument [Line Items]
Borrowings under credit facilities	$ 140,000
Preferred stock | Viom preferred shares
Debt Instrument [Line Items]
Financial instrument, maximum settlement amount classified as short term debt		12,500				12,500		₨ 800
Secured Debt | Series 2010-1 Class C
Debt Instrument [Line Items]
Current portion of long-term obligations		$ 67,400				$ 67,400
Secured Debt | Viom Term Loan | Minimum
Debt Instrument [Line Items]
Debt instrument, term (in years)						1 year
Prepayment penalty, as a percent of principal (as a percent)						1.00%
Repayment period (in months)						6 months
Long-term debt, stated interest rate (as a percent)		10.50%				10.50%		10.50%
Secured Debt | Viom Term Loan | Minimum | Marginal Cost of Funds based Lending Rate
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)						1.00%
Secured Debt | Viom Term Loan | Maximum
Debt Instrument [Line Items]
Debt instrument, term (in years)						10 years
Prepayment penalty, as a percent of principal (as a percent)						2.00%
Repayment period (in months)						36 months
Long-term debt, stated interest rate (as a percent)		11.20%				11.20%		11.20%
Secured Debt | Viom Term Loan | Maximum | Marginal Cost of Funds based Lending Rate
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)						1.55%
Secured Debt | Viom Debenture
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		9.90%				9.90%		9.90%
Secured Debt | Viom Debenture | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)						0.60%
Basis spread on variable rate, reset rate (as a percent)						10.00%
Basis spread on variable rate, first reset period (as a percent)						36 months
Basis spread on variable rate, second reset period (as a percent)						48 months
Secured Debt | Viom Debenture | Minimum | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate, reset threshold (as a percent)						9.75%
Secured Debt | Viom Debenture | Maximum | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate, reset threshold (as a percent)						10.25%
Revolving Credit Facility | Viom Working Capital Facilities | Minimum
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		9.85%				9.85%		9.85%
Revolving Credit Facility | Viom Working Capital Facilities | Maximum
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		11.80%				11.80%		11.80%
Mandatorily Redeemable Preferred Stock | Viom preferred shares
Debt Instrument [Line Items]
Preferred stock, shares outstanding | shares		166,666,666				166,666,666		166,666,666
Financial instrument, maximum settlement amount		$ 25,000				$ 25,000		₨ 1,670
Number of redemption installments | installment						2
Preferred stock, redemption price (in INR per share) | ₨ / shares								₨ 10
Preferred stock, dividend rate percentage (in percent)						13.50%
Redemption price (as a percent)						2.00%
Senior Notes
Debt Instrument [Line Items]
Redemption price (as a percent)						100.00%
Conditional repurchase price as percent of principal		101.00%				101.00%		101.00%
Maximum Adjusted EBITDA		3.5				3.5		3.5
Senior Notes | 3.30% and 4.40% Senior Notes
Debt Instrument [Line Items]
Proceeds from issuance of senior notes, net				$ 1,237,200
Senior Notes | 3.30% Senior Notes
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		3.30%		3.30%		3.30%		3.30%	3.30%
Principal amount				$ 750,000
Senior Notes | 4.40% Senior Notes
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		4.40%		4.40%		4.40%		4.40%	4.40%
Principal amount				$ 500,000
Senior Notes | 3.375% Senior Notes
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		3.375%	3.375%			3.375%		3.375%	3.375%
Principal amount			$ 1,000,000
Proceeds from issuance of senior notes, net			$ 981,500
Senior Notes | 2.250% Senior Notes
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		2.25%				2.25%		2.25%	2.25%
Effective interest rate (as a percent)		1.75%				1.75%		1.75%
Principal amount		$ 600,000				$ 600,000
Senior Notes | 3.125% Senior Notes
Debt Instrument [Line Items]
Long-term debt, stated interest rate (as a percent)		3.125%				3.125%		3.125%	3.125%
Principal amount		$ 400,000				$ 400,000
Proceeds from issuance of senior notes, net		990,600
Unsecured Debt | Viom Debt
Debt Instrument [Line Items]
Current portion of long-term obligations		53,500				53,500
Short-term committed loan facility borrowing capacity		87,100				87,100
Repayments of outstanding debt						21,000
Unsecured Debt | Viom Debt | Subsequent Event
Debt Instrument [Line Items]
Current portion of long-term obligations | ₨					₨ 3,600
Short-term committed loan facility borrowing capacity | ₨					5,800
Repayments of outstanding debt | ₨					₨ 1,400
Unsecured Debt | Term Loan 2013
Debt Instrument [Line Items]
Principal amount		1,000,000				1,000,000
Repayments of indebtedness under the Term Loan						1,000,000
Viom Transaction
Debt Instrument [Line Items]
Current portion of long-term obligations		$ 108,400				$ 108,400		₨ 7,200

FAIR VALUE MEASUREMENTS - ASSET

FAIR VALUE MEASUREMENTS - ASSETS AND LIABILITIES MEASURED AT FAIR VALUE ON A RECURRING BASIS (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Embedded derivative in lease agreement	$ 0	$ 0
Acquisition-related contingent consideration	0	0
Fair Value, Inputs, Level 2 | Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements	212	692
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Embedded derivative in lease agreement	13,513	14,176
Acquisition-related contingent consideration	21,575	12,436
Fair Value, Inputs, Level 3 | Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements	$ 0	$ 0

FAIR VALUE MEASUREMENTS - NARRA

FAIR VALUE MEASUREMENTS - NARRATIVE (Details) - USD ($)	Sep. 30, 2016	Apr. 21, 2016	Dec. 31, 2015
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	47,700,000
Redeemable Noncontrolling Interest, Equity, Fair Value		$ 1,100,000,000
Debt, long-term and short-term, combined amount	18,679,136,000		$ 17,119,009,000
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	19,500,000,000		17,400,000,000
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	12,300,000,000		8,700,000,000
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	$ 7,200,000,000		$ 8,700,000,000
Senior Notes | 2.250% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, stated interest rate (as a percent)	2.25%		2.25%
Interest Rate Swap | Senior Notes | 2.250% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, notional amount	$ 600,000,000
South Africa
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business combination, contingent consideration arrangements, range of outcomes, value, high	$ 22,200,000

INCOME TAXES - NARRATIVE (Detai

INCOME TAXES - NARRATIVE (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Income Tax Contingency [Line Items]
Unrecognized tax benefits that would impact the ETR	$ 74,700,000		$ 74,700,000		$ 28,100,000
Unrecognized tax benefits, increase resulting from current period tax positions	8,400,000		47,700,000
Unrecognized tax benefits, increase resulting from acquisition			23,800,000
Unrecognized tax benefits, reduction resulting from lapse of applicable statute of limitations	1,800,000		1,800,000
Unrecognized tax benefits, income tax penalties and interest	1,800,000	$ 700,000	7,000,000	$ 2,300,000
Unrecognized tax benefits, decrease in income tax penalties and interest expense resulting from lapse of applicable statute of limitations	1,600,000	$ 3,100,000	1,600,000	$ 3,100,000
Unrecognized tax benefits, income tax penalties and interest accrued	24,500,000		24,500,000		$ 20,200,000
Minimum
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	0		0
Maximum
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 12,400,000		$ 12,400,000

STOCK-BASED COMPENSATION - SUMM

STOCK-BASED COMPENSATION - SUMMARY OF STOCK-BASED COMPENSATION EXPENSE (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based compensation expense	$ 20,226	$ 18,345	$ 70,212	$ 72,251
Stock-based compensation expense capitalized as property and equipment	$ 353	$ 495	$ 1,115	$ 1,554

STOCK-BASED COMPENSATION - ASSU

STOCK-BASED COMPENSATION - ASSUMPTIONS USED TO DETERMINE THE GRANT DATE FAIR VALUE FOR OPTIONS GRANTED (Details) - Employee Stock Option	9 Months Ended
	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum range of risk-free interest rate	1.00%
Maximum range of risk-free interest rate	1.73%
Weighted average risk-free interest rate	1.45%
Minimum range of expected volatility of underlying stock price	20.64%
Maximum range of expected volatility of underlying stock price	21.45%
Weighted average expected volatility of underlying stock price	21.45%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of expected life of stock options	4 years 6 months
Range of expected annual dividend yield	1.85%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of expected life of stock options	5 years 2 months 12 days
Range of expected annual dividend yield	2.40%

STOCK-BASED COMPENSATION - SU54

STOCK-BASED COMPENSATION - SUMMARY OF THE COMPANY'S OPTION ACTIVITY (Details) - Employee Stock Option	9 Months Ended
	Sep. 30, 2016shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding as of January 1, 2016 (in shares)	7,680,819
Granted (in shares)	1,140,366
Exercised (in shares)	(1,263,309)
Forfeited (in shares)	(16,320)
Expired (in shares)	(800)
Outstanding as of September 30, 2016 (in shares)	7,540,756

STOCK-BASED COMPENSATION - SU55

STOCK-BASED COMPENSATION - SUMMARY OF THE COMPANY'S RESTRICTED STOCK UNIT ACTIVITY (Details) - shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2016
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding as of January 1, 2016 (in shares)	1,656,993
Granted (in shares)	774,739
Vested (in shares)	(641,810)
Forfeited (in shares)	(84,461)
Outstanding as of September 30, 2016 (in shares)	1,656,993	1,705,461
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding as of January 1, 2016 (in shares)	33,377
Granted (in shares)	192,719
Vested (in shares)	0
Forfeited (in shares)	0
Outstanding as of September 30, 2016 (in shares)	33,377	226,096
Vesting period	3 years

STOCK-BASED COMPENSATION - NARR

STOCK-BASED COMPENSATION - NARRATIVE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ESPP, discount rate (as a percent)			15.00%
Stock-based compensation expense	$ 20,226	$ 18,345	$ 70,212	$ 72,251
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense	100,600		$ 100,600
Expected recognition of stock award compensation expense weighted average period in years			2 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Total unrecognized compensation expense	14,200		$ 14,200
Expected recognition of stock award compensation expense weighted average period in years			2 years
Three year performance grant, shares granted			169,340	70,135
Shares granted, grant date fair value not yet established			23,377
Stock-based compensation expense	2,300		$ 5,500
Performance Shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares			0.00%
Performance Shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares			200.00%
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)			$ 14.57
Total unrecognized compensation expense	$ 30,100		$ 30,100
Expected recognition of stock award compensation expense weighted average period in years			2 years
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issuable under stock incentive plan	9,500,000		9,500,000
2007 Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
2007 Plan | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
2007 Plan | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Expiration period			10 years

REDEEMABLE NONCONTROLLING INT57

REDEEMABLE NONCONTROLLING INTERESTS (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016USD ($)	Sep. 30, 2016₨ / shares	Dec. 31, 2015USD ($)
Noncontrolling Interest [Abstract]
Temporary equity, redemption price per share (in dollars per share) | ₨ / shares		₨ 216
Changes In Redeemable Noncontrolling Interests [Roll Forward]
Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests			$ 0
Fair value at acquisition	$ 1,100,804
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	1,536
Foreign currency translation adjustment attributable to noncontrolling interests	(2,138)
Mandatory redeemable preference shares, value	$ 1,100,202		$ 0

EQUITY - DISTRIBUTIONS (Detail)

EQUITY - DISTRIBUTIONS (Detail) - USD ($) $ / shares in Units, $ in Thousands	Sep. 16, 2016	Jul. 22, 2016	Jun. 02, 2016	Apr. 16, 2016	Mar. 09, 2016	Jan. 14, 2016	Dec. 03, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Dividends Payable [Line Items]
Distribution per common share (in dollars per share)								$ 0.55	$ 0.46	$ 1.59	$ 1.32
Distributions paid on common stock										$ 651,966	$ 516,012
Distributions paid on preferred stock										$ 80,344	$ 57,866
Common Stock
Dividends Payable [Line Items]
Distribution per common share (in dollars per share)	$ 0.55		$ 0.53		$ 0.51		$ 0.49
Distributions paid on common stock	$ 234,100		$ 225,400		$ 216,500		$ 207,700
Series A Preferred Stock | Convertible Preferred Stock Subject to Mandatory Redemption
Dividends Payable [Line Items]
Distribution per preferred share (in dollars per share)		$ 1.3125		$ 1.3125		$ 1.3125
Distributions paid on preferred stock		$ 7,900		$ 7,900		$ 7,900
Series B Preferred Stock | Convertible Preferred Stock Subject to Mandatory Redemption
Dividends Payable [Line Items]
Distribution per preferred share (in dollars per share)		$ 13.75		$ 13.75		$ 13.75
Distributions paid on preferred stock		$ 18,900		$ 18,900		$ 18,900

EQUITY - NARRATIVE (Details)

EQUITY - NARRATIVE (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Class of Stock [Line Items]
Proceeds from stock options and ESPP	$ 76,601	$ 29,324
Accrued dividend RSU	5,800
Dividends Declared and Paid
Class of Stock [Line Items]
Paid dividend RSU	$ 2,400
Series B Preferred Stock
Class of Stock [Line Items]
Depository shares, percentage of preferred shares	0.1
Convertible Preferred Stock Subject to Mandatory Redemption | Series A Preferred Stock | Minimum
Class of Stock [Line Items]
Conversion factor, preferred stock	0.9272
Convertible Preferred Stock Subject to Mandatory Redemption | Series A Preferred Stock | Maximum
Class of Stock [Line Items]
Conversion factor, preferred stock	1.1591
Convertible Preferred Stock Subject to Mandatory Redemption | Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, liquidation preference per share (in dollars per share)	$ 1,000
Shares issued, price per share (in dollars per share)	$ 100
Convertible Preferred Stock Subject to Mandatory Redemption | Series B Preferred Stock | Minimum
Class of Stock [Line Items]
Conversion factor, preferred stock	8.5911
Convertible Preferred Stock Subject to Mandatory Redemption | Series B Preferred Stock | Maximum
Class of Stock [Line Items]
Conversion factor, preferred stock	10.3093
Convertible Preferred Stock Subject to Mandatory Redemption | Preferred stock
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01		$ 0.01
Convertible Preferred Stock Subject to Mandatory Redemption | Preferred stock | Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares issued	6,000,000		6,000,000
Preferred stock, dividend rate percentage (in percent)	5.25%		5.25%
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, liquidation preference per share (in dollars per share)	$ 100
Convertible Preferred Stock Subject to Mandatory Redemption | Preferred stock | Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares issued	1,375,000		1,375,000
Preferred stock, dividend rate percentage (in percent)	5.50%		5.50%
Preferred stock, par value (in dollars per share)	$ 0.01
Depository shares, amount issued	13,750,000

EARNINGS PER COMMON SHARE - SCH

EARNINGS PER COMMON SHARE - SCHEDULE OF EARNINGS PER BASIC AND DILUTED BY COMMON CLASS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Earnings Per Share [Abstract]
Net income attributable to American Tower Corporation stockholders	$ 264,509	$ 102,999	$ 727,218	$ 452,372
Dividends on preferred stock	(26,781)	(26,781)	(80,344)	(63,382)
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION COMMON STOCKHOLDERS	$ 237,728	$ 76,218	$ 646,874	$ 388,990
Basic weighted average common shares outstanding (in shares)	425,517	423,375	424,831	417,280
Dilutive securities (in shares)	4,408	3,852	4,188	4,072
Diluted weighted average common shares outstanding (in shares)	429,925	427,227	429,019	421,352
Basic net income attributable to American Tower Corporation common stockholders per common share (in dollars per share)	$ 0.56	$ 0.18	$ 1.52	$ 0.93
Diluted net income attributable to American Tower Corporation common stockholders per common share (in dollars per share)	$ 0.55	$ 0.18	$ 1.51	$ 0.92

EARNINGS PER COMMON SHARE - S61

EARNINGS PER COMMON SHARE - SCHEDULE OF SHARES EXCLUDED FROM COMPUTATION OF EARNINGS PER SHARE (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Restricted stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issuable upon conversion of the stock-based awards and convertible notes	0	0	2	0
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issuable upon conversion of the stock-based awards and convertible notes	8	1,996	1,619	1,472
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	17,473	17,368	17,473	14,724

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - FUTURE MINIMUM RENTAL RECEIPTS UNDER OPERATING LEASE AGREEMENTS (Details) $ in Millions	Sep. 30, 2016USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2016	$ 1,271
2,017	4,710
2,018	4,543
2,019	4,269
2,020	3,916
Thereafter	13,825
Total	$ 32,534

COMMITMENTS AND CONTINGENCIES63

COMMITMENTS AND CONTINGENCIES - FUTURE MINIMUM RENTAL PAYMENTS UNDER NON-CANCELABLE OPERATING LEASES (Details) $ in Millions	Sep. 30, 2016USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2016	$ 244
2,017	912
2,018	886
2,019	854
2,020	815
Thereafter	7,370
Total	$ 11,081

COMMITMENTS AND CONTINGENCIES64

COMMITMENTS AND CONTINGENCIES - NARRATIVE (Details)	Mar. 27, 2015USD ($)communications_siterenewal_period	Dec. 31, 2000tower	Sep. 30, 2016USD ($)towerrenewal_periodshares
Loss Contingencies [Line Items]
Lessor agreements, term of contract			10 years
Verizon Transaction
Loss Contingencies [Line Items]
Capital leased assets, number of units (in number of communication sites) | communications_site	11,286
Right to lease, weighted average term	28 years
Aggregate purchase option price for towers | $	$ 5,000,000,000
Customer lease, initial term	10 years
Successive terms to renew lease (in numbers of terms) | renewal_period	8
Renewal term	5 years
AT&T Transaction
Loss Contingencies [Line Items]
Capital leased assets, number of units (in number of communication sites) | tower			2,370
Aggregate purchase option price for towers | $			$ 748,300,000
Successive terms to renew lease (in numbers of terms) | renewal_period			4
Operating lease, term of contract			27 years
Number of communications sites acquired (in number of towers) | tower			60
Purchase price accretion rate (per year)			10.00%
AT&T Transaction | Commitments prior to June 30, 2020
Loss Contingencies [Line Items]
Renewal term			5 years
AT&T Transaction | Commitments subsequent to June 30, 2020
Loss Contingencies [Line Items]
Renewal term			1 year
ALLTEL Transaction
Loss Contingencies [Line Items]
Capital leased assets, number of units (in number of communication sites) | tower		1,800
Aggregate purchase option price for towers | $			$ 75,700,000
Number of communications sites acquired (in number of towers) | tower			1,525
Average lease term (in years)		15 years
Cash purchase price per tower | $			$ 42,844
Purchase price of tower in shares of common stock (in shares) | shares			769

ACQUISITIONS - SCHEDULE OF MERG

ACQUISITIONS - SCHEDULE OF MERGER AND ACQUISITION RELATED COSTS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Business Combinations [Abstract]
Acquisition and merger related expenses	$ 1,124	$ 8,587	$ 7,844	$ 16,574
Integration costs	$ 1,846	$ 5,938	$ 8,351	$ 12,218

ACQUISITIONS - SCHEDULE OF PREL

ACQUISITIONS - SCHEDULE OF PRELIMINARY ALLOCATION OF THE PURCHASE PRICE (Details) $ in Thousands, ₨ in Billions	Apr. 21, 2016USD ($)	Apr. 21, 2016INR (₨)	Dec. 16, 2015USD ($)	Sep. 30, 2015USD ($)	Apr. 29, 2015USD ($)	Sep. 30, 2016USD ($)	Dec. 31, 2015USD ($)
Business Acquisition [Line Items]
Goodwill						$ 4,997,224	$ 4,091,805
Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life (in years)						20 years	20 years
Viom Transaction
Business Acquisition [Line Items]
Goodwill						$ 826,700
Debt assumed	$ (800,000)	₨ (52.3)
Viom Transaction | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Current assets						281,888
Non-current assets						37,737
Property and equipment						707,560
Customer-related intangible assets						1,435,164
Network location intangible assets						691,484
Current liabilities						(181,101)
Deferred tax liability						(657,810)
Other non-current liabilities						(105,458)
Net assets acquired						2,209,464
Goodwill						826,735
Fair value of net assets acquired						3,036,199
Debt assumed						(786,889)
Redeemable noncontrolling interests						(1,100,804)
Purchase Price	$ 1,100,000	₨ 76.4				1,148,506
Other Acquisition 2016 | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Current assets						12,619
Non-current assets						145
Property and equipment						46,026
Customer-related intangible assets						86,779
Network location intangible assets						21,258
Current liabilities						(7,701)
Deferred tax liability						(14,290)
Other non-current liabilities						(6,477)
Net assets acquired						138,359
Goodwill						47,200
Fair value of net assets acquired						185,559
Debt assumed						0
Redeemable noncontrolling interests						0
Purchase Price						185,559
TIM Acquisition | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Current assets							$ 0
Non-current assets							0
Property and equipment							275,630
Customer-related intangible assets							361,822
Network location intangible assets							115,562
Current liabilities							(3,192)
Deferred tax liability							0
Other non-current liabilities							(74,966)
Net assets acquired							674,856
Goodwill							122,011
Fair value of net assets acquired							796,867
Debt assumed							0
Purchase Price			$ 21,700	$ 130,900	$ 644,300		796,867
TIM Acquisition | Adjusted Purchase Price Allocation
Business Acquisition [Line Items]
Current assets						0
Non-current assets						0
Property and equipment						274,530
Customer-related intangible assets						361,765
Network location intangible assets						115,795
Current liabilities						(3,192)
Deferred tax liability						0
Other non-current liabilities						(74,966)
Net assets acquired						673,932
Goodwill						122,116
Fair value of net assets acquired						796,048
Debt assumed						0
Purchase Price						796,048
Other Acquisition 2015 | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Current assets							1,113
Non-current assets							995
Property and equipment							42,716
Customer-related intangible assets							63,001
Network location intangible assets							37,691
Current liabilities							(624)
Deferred tax liability							0
Other non-current liabilities							(4,028)
Net assets acquired							140,864
Goodwill							24,011
Fair value of net assets acquired							164,875
Debt assumed							0
Purchase Price							$ 164,875
Other Acquisition 2015 | Adjusted Purchase Price Allocation
Business Acquisition [Line Items]
Current assets						1,113
Non-current assets						995
Property and equipment						42,716
Customer-related intangible assets						62,832
Network location intangible assets						37,691
Current liabilities						(624)
Deferred tax liability						0
Other non-current liabilities						(4,028)
Net assets acquired						140,695
Goodwill						24,011
Fair value of net assets acquired						164,706
Debt assumed						0
Purchase Price						$ 164,706
Maximum | Acquired Network Location
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life (in years)						20 years	20 years
Maximum | Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life (in years)						20 years

ACQUISITIONS - PRO FORMA INFORM

ACQUISITIONS - PRO FORMA INFORMATION (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Business Acquisition, Pro Forma Information [Abstract]
Pro forma operating revenues	$ 1,517,197	$ 1,449,460	$ 4,498,458	$ 4,372,304
Pro forma net income attributable to American Tower Corporation	$ 238,364	$ 72,885	$ 643,780	$ 346,097
Basic net income attributable to American Tower Corporation common stockholders (in dollars per share)	$ 0.56	$ 0.17	$ 1.52	$ 0.82
Diluted net income attributable to American Tower Corporation common stockholders (in dollars per share)	$ 0.55	$ 0.17	$ 1.50	$ 0.81

ACQUISITIONS - NARRATIVE (Detai

ACQUISITIONS - NARRATIVE (Details) $ in Thousands, ₨ in Billions	Apr. 21, 2016USD ($)sitesystem	Apr. 21, 2016INR (₨)	Mar. 17, 2016USD ($)site	Dec. 16, 2015USD ($)communications_site	Sep. 30, 2015USD ($)communications_site	Apr. 29, 2015USD ($)communications_site	Sep. 30, 2016USD ($)sitecommunications_site	Sep. 30, 2016USD ($)sitecommunications_site	Dec. 31, 2015USD ($)	Apr. 21, 2016INR (₨)sitesystem
Business Acquisition [Line Items]
Revenue of acquiree since acquisition date							$ 208,100	$ 366,100
Gross margin of acquiree since acquisition date							87,900	153,100
Mandatory redeemable preference shares, value							1,100,202	1,100,202	$ 0
Accounts payable							$ 105,551	105,551	96,714
Viom Transaction
Business Acquisition [Line Items]
Percentage of voting interest acquired (as a percent)	51.00%									51.00%
Number of communications sites acquired (in number of towers) | site	42,000									42,000
Distributed antenna systems acquired (systems) | system	200									200
Fair value of debt assumed through acquisitions	$ 800,000	₨ 52.3
Viom Transaction | Mandatorily Redeemable Preferred Stock
Business Acquisition [Line Items]
Mandatory redeemable preference shares, value	25,100									₨ 1.7
Viom Transaction | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price	$ 1,100,000	₨ 76.4						1,148,506
Fair value of debt assumed through acquisitions								$ 786,889
Other Acquisition 2016
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | site							784	784
Contingent consideration							$ 8,700	$ 8,700
Accounts payable							$ 2,100	2,100
Other Acquisition 2016 | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price								185,559
Fair value of debt assumed through acquisitions								$ 0
TIM Acquisition
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | communications_site				182	1,125	4,176	5,301	5,301
Aggregate purchase price adjustment								$ 800
TIM Acquisition | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price				$ 21,700	$ 130,900	$ 644,300			796,867
Fair value of debt assumed through acquisitions									0
TIM Acquisition | Adjusted Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price								796,048
Fair value of debt assumed through acquisitions								0
Airtel Tanzania
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | site			1,350
Airtel Tanzania | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price			$ 179,000
Additional sites to be acquired | site			100
Other Acquisition 2015 | Preliminary Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price									164,875
Fair value of debt assumed through acquisitions									$ 0
Other Acquisition 2015 | Adjusted Purchase Price Allocation
Business Acquisition [Line Items]
Purchase Price								164,706
Fair value of debt assumed through acquisitions								0
Aggregate purchase price adjustment								$ 200

BUSINESS SEGMENTS - SUMMARIZED

BUSINESS SEGMENTS - SUMMARIZED FINANCIAL INFORMATION CONCERNING THE COMPANY'S REPORTABLE SEGMENTS (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)segment	Sep. 30, 2015USD ($)	Dec. 31, 2015USD ($)segment
Segment Reporting, Measurement Disclosures [Abstract]
Number of reportable segments | segment			5		3
Segment Reporting Information [Line Items]
Segment revenues	$ 1,514,845	$ 1,237,910	$ 4,246,119	$ 3,491,475
Segment operating expenses	490,639	364,894	1,300,490	950,933
Segment gross margin	1,026,948	876,009	2,953,835	2,548,793
Segment selling, general, administrative and development expense	81,694	68,233	243,761	195,545
Segment operating profit	945,254	807,776	2,710,074	2,353,248
Stock-based compensation expense	20,226	18,345	70,212	72,251
Other selling, general, administrative and development expense	30,215	28,749	93,016	88,218
Depreciation, amortization and accretion	397,999	341,096	1,137,398	932,972
Other expense	211,042	227,611	577,271	677,332
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	285,772	191,975	832,177	582,475
Total assets	30,655,527	26,926,788	30,655,527	26,926,788	$ 26,904,272
Operating Expense
Segment Reporting Information [Line Items]
Stock-based compensation expense	600	500	1,900	1,600
Selling General Administrative And Development Expense
Segment Reporting Information [Line Items]
Stock-based compensation expense	19,628	17,850	68,309	70,697
TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	2,742	2,993	8,206	8,251
Operating Segments | Property
Segment Reporting Information [Line Items]
Segment revenues	1,497,936	1,212,849	4,191,779	3,429,264
Segment operating expenses	485,099	355,686	1,279,061	928,406
Segment gross margin	1,015,579	860,156	2,920,924	2,509,109
Segment selling, general, administrative and development expense	78,968	64,503	234,773	184,940
Segment operating profit	936,611	795,653	2,686,151	2,324,169
Total assets	30,456,053	26,703,371	30,456,053	26,703,371
Operating Segments | Property | TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	2,742	2,993	8,206	8,251
Operating Segments | Property | United States
Segment Reporting Information [Line Items]
Segment revenues	837,002	807,978	2,518,426	2,328,699
Segment operating expenses	188,777	187,368	548,875	502,572
Segment gross margin	648,225	620,610	1,969,551	1,826,127
Segment selling, general, administrative and development expense	35,526	31,374	107,533	89,439
Segment operating profit	612,699	589,236	1,862,018	1,736,688
Total assets	18,837,629	19,353,820	18,837,629	19,353,820
Operating Segments | Property | United States | TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	0	0	0	0
Operating Segments | Property | Asia
Segment Reporting Information [Line Items]
Segment revenues	269,907	61,563	557,734	178,699
Segment operating expenses	154,139	32,629	315,074	93,917
Segment gross margin	115,768	28,934	242,660	84,782
Segment selling, general, administrative and development expense	15,030	5,824	36,376	17,133
Segment operating profit	100,738	23,110	206,284	67,649
Total assets	4,612,766	746,355	4,612,766	746,355
Operating Segments | Property | Asia | TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	0	0	0	0
Operating Segments | Property | EMEA
Segment Reporting Information [Line Items]
Segment revenues	130,664	124,545	395,066	270,754
Segment operating expenses	53,787	57,492	167,908	110,205
Segment gross margin	76,877	67,053	227,158	160,549
Segment selling, general, administrative and development expense	12,958	13,009	45,795	33,820
Segment operating profit	63,919	54,044	181,363	126,729
Total assets	2,120,592	2,301,888	2,120,592	2,301,888
Operating Segments | Property | EMEA | TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	0	0	0	0
Operating Segments | Property | Latin America
Segment Reporting Information [Line Items]
Segment revenues	260,363	218,763	720,553	651,112
Segment operating expenses	88,396	78,197	247,204	221,712
Segment gross margin	174,709	143,559	481,555	437,651
Segment selling, general, administrative and development expense	15,454	14,296	45,069	44,548
Segment operating profit	159,255	129,263	436,486	393,103
Total assets	4,885,066	4,301,308	4,885,066	4,301,308
Operating Segments | Property | Latin America | TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	2,742	2,993	8,206	8,251
Operating Segments | Services
Segment Reporting Information [Line Items]
Segment revenues	16,909	25,061	54,340	62,211
Segment operating expenses	5,540	9,208	21,429	22,527
Segment gross margin	11,369	15,853	32,911	39,684
Segment selling, general, administrative and development expense	2,726	3,730	8,988	10,605
Segment operating profit	8,643	12,123	23,923	29,079
Total assets	60,810	70,006	60,810	70,006
Operating Segments | Services | TV Azteca
Segment Reporting Information [Line Items]
Interest income, TV Azteca, net	0	0	0	0
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Stock-based compensation expense	20,226	18,345	70,212	72,251
Other selling, general, administrative and development expense	30,215	28,749	93,016	88,218
Depreciation, amortization and accretion	397,999	341,096	1,137,398	932,972
Other expense	211,042	227,611	577,271	677,332
Total assets	$ 138,664	153,411	$ 138,664	153,411
Amount previously recorded as segment selling, general and administrative expense		1,600		3,800
Corporate, Non-Segment | Restatement Adjustment
Segment Reporting Information [Line Items]
Total assets		$ 12,000		$ 12,000

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - ATC Europe - PGGM - Forecast € in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2016USD ($)	Dec. 31, 2016EUR (€)
Subsequent Event [Line Items]
Joint venture purchase price	$ 270.2	€ 248.2
Subsequent Event
Subsequent Event [Line Items]
Ownership interest (as a percent)	49.00%	49.00%