American Tower (AMT) 10-Q 30 Apr 24 2024 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2024	Apr. 23, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-14195
Entity Registrant Name	AMERICAN TOWER CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	65-0723837
Entity Address, Address Line One	116 Huntington Avenue
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02116
City Area Code	617
Local Phone Number	375-7500
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		466,975,019
Entity Central Index Key	0001053507
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false
Common Stock, $0.01 par value
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	AMT
Security Exchange Name	NYSE
1.375% Senior Notes due 2025
Document Information [Line Items]
Title of 12(b) Security	1.375% Senior Notes due 2025
Trading Symbol	AMT 25A
Security Exchange Name	NYSE
1.950% Senior Notes due 2026
Document Information [Line Items]
Title of 12(b) Security	1.950% Senior Notes due 2026
Trading Symbol	AMT 26B
Security Exchange Name	NYSE
0.450% Senior Notes due 2027
Document Information [Line Items]
Title of 12(b) Security	0.450% Senior Notes due 2027
Trading Symbol	AMT 27C
Security Exchange Name	NYSE
0.400% Senior Notes due 2027
Document Information [Line Items]
Title of 12(b) Security	0.400% Senior Notes due 2027
Trading Symbol	AMT 27D
Security Exchange Name	NYSE
4.125% Senior Notes due 2027
Document Information [Line Items]
Title of 12(b) Security	4.125% Senior Notes due 2027
Trading Symbol	AMT 27F
Security Exchange Name	NYSE
0.500% Senior Notes due 2028
Document Information [Line Items]
Title of 12(b) Security	0.500% Senior Notes due 2028
Trading Symbol	AMT 28A
Security Exchange Name	NYSE
0.875% Senior Notes due 2029
Document Information [Line Items]
Title of 12(b) Security	0.875% Senior Notes due 2029
Trading Symbol	AMT 29B
Security Exchange Name	NYSE
0.950% Senior Notes due 2030
Document Information [Line Items]
Title of 12(b) Security	0.950% Senior Notes due 2030
Trading Symbol	AMT 30C
Security Exchange Name	NYSE
4.625% Senior Notes due 2031
Document Information [Line Items]
Title of 12(b) Security	4.625% Senior Notes due 2031
Trading Symbol	AMT 31B
Security Exchange Name	NYSE
1.000% Senior Notes due 2032
Document Information [Line Items]
Title of 12(b) Security	1.000% Senior Notes due 2032
Trading Symbol	AMT 32
Security Exchange Name	NYSE
1.250% Senior Notes due 2033
Document Information [Line Items]
Title of 12(b) Security	1.250% Senior Notes due 2033
Trading Symbol	AMT 33
Security Exchange Name	NYSE

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
CURRENT ASSETS:
Cash and cash equivalents	$ 2,389.1	$ 1,973.3
Restricted cash	127.6	120.1
Accounts receivable, net	738.4	669.7
Prepaid and other current assets	984.6	946.9
Total current assets	4,239.7	3,710
PROPERTY AND EQUIPMENT, net	20,094.2	19,788.8
GOODWILL	12,556.8	12,639
OTHER INTANGIBLE ASSETS, net	16,119.3	16,520.7
DEFERRED TAX ASSET	161.2	179.1
DEFERRED RENT ASSET	3,596.8	3,521.8
RIGHT-OF-USE ASSET	9,199.8	8,878.8
NOTES RECEIVABLE AND OTHER NON-CURRENT ASSETS	711.2	789.4
TOTAL	66,679	66,027.6
CURRENT LIABILITIES:
Accounts payable	182.1	258.7
Accrued expenses	1,134.1	1,280.6
Distributions payable	776.7	906.2
Accrued interest	309.9	387
Current portion of operating lease liability	715.2	794.6
Current portion of long-term obligations	3,067.6	3,187.5
Unearned revenue	544.2	434.7
Total current liabilities	6,729.8	7,249.3
LONG-TERM OBLIGATIONS	36,191.9	35,734
OPERATING LEASE LIABILITY	7,866.3	7,438.7
ASSET RETIREMENT OBLIGATIONS	2,607.1	2,158.2
DEFERRED TAX LIABILITY	1,394.4	1,361.4
OTHER NON-CURRENT LIABILITIES	1,227.8	1,220.6
Total liabilities	56,017.3	55,162.2
COMMITMENTS AND CONTINGENCIES
EQUITY (shares in thousands):
Common stock: $0.01 par value; 1,000,000 shares authorized; 477,968 and 477,300 shares issued; and 466,964 and 466,296 shares outstanding, respectively	4.8	4.8
Additional paid-in capital	14,903.4	14,872.9
Distributions in excess of earnings	(3,481.2)	(3,638.8)
Accumulated other comprehensive loss	(6,078)	(5,739.5)
Treasury stock (11,004 shares at cost)	(1,301.2)	(1,301.2)
Total American Tower Corporation equity	4,047.8	4,198.2
Noncontrolling interests	6,613.9	6,667.2
Total equity	10,661.7	10,865.4
TOTAL	$ 66,679	$ 66,027.6

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	477,968,000	477,300,000
Common stock, shares outstanding (in shares)	466,964,000	466,296,000
Treasury stock, shares (in shares)	11,004,000	11,004,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
REVENUES:
Total operating revenues	$ 2,834.1	$ 2,767.2
Costs of operations (exclusive of items shown separately below):
Property	774.4	787
Depreciation, amortization and accretion	549.4	794.1
Selling, general, administrative and development expense	257	263.9
Other operating expenses	2.8	127.5
Total operating expenses	1,597.5	1,991.6
OPERATING INCOME	1,236.6	775.6
OTHER INCOME (EXPENSE):
Interest income	48	30.8
Interest expense	(366.7)	(340.2)
Other income (expense) (including foreign currency gains (losses) of $127.6 and $(84.1), respectively)	113	(97.8)
Total other expense	(205.7)	(407.2)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	1,030.9	368.4
Income tax provision	(109.2)	(53.4)
NET INCOME	921.7	315
Net (income) loss attributable to noncontrolling interests	(4.3)	20.8
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION COMMON STOCKHOLDERS, BASIC	917.4	335.8
NET INCOME ATTRIBUTABLE TO AMERICAN TOWER CORPORATION COMMON STOCKHOLDERS, DILUTED	$ 917.4	$ 335.8
Earnings Per Share [Abstract]
Basic net income attributable to American Tower Corporation common stockholders (in dollars per share)	$ 1.97	$ 0.72
Diluted net income attributable to American Tower Corporation common stockholders (in dollars per share)	$ 1.96	$ 0.72
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING (in thousands):
BASIC (in shares)	466,519	465,741
DILUTED (in shares)	467,660	466,810
Property
REVENUES:
Total operating revenues	$ 2,803.9	$ 2,714.5
Services
REVENUES:
Total operating revenues	30.2	52.7
Costs of operations (exclusive of items shown separately below):
Services	$ 13.9	$ 19.1

CONSOLIDATED STATEMENTS OF OP_2

CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Foreign currency gains (losses)	$ 127.6	$ (84.1)

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 921.7	$ 315
Other comprehensive (loss) income:
Foreign currency translation adjustments, net of tax benefit of $(0.2) and $(0.0), respectively	(431.2)	232.1
Other comprehensive (loss) income	(431.2)	232.1
Comprehensive income	490.5	547.1
Comprehensive loss (income) attributable to noncontrolling interests	88.4	(19.1)
Comprehensive income attributable to American Tower Corporation stockholders	$ 578.9	$ 528

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax benefit	$ (0.2)	$ 0

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 921.7	$ 315
Adjustments to reconcile net income to cash provided by operating activities
Depreciation, amortization and accretion	549.4	794.1
Stock-based compensation expense	64.9	65.5
Other non-cash items reflected in statements of operations	(41.8)	235.3
Increase in net deferred rent balances	(79)	(112)
Right-of-use asset and Operating lease liability, net	8.8	(44.9)
Changes in unearned revenue	130.4	96.2
Increase in assets	(99.3)	(170.1)
Decrease in liabilities	(171.5)	(108.6)
Cash provided by operating activities	1,283.6	1,070.5
CASH FLOWS FROM INVESTING ACTIVITIES
Payments for purchase of property and equipment and construction activities	(396.7)	(461.9)
Payments for acquisitions, net of cash acquired	(44.7)	(60.9)
Proceeds from sale of short-term investments and other non-current assets	6	3.1
Deposits and other	(0.7)	242.9
Cash used for investing activities	(436.1)	(276.8)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from short-term borrowings, net	8.7	154.1
Borrowings under credit facilities	2,790.5	1,745
Proceeds from issuance of senior notes, net	1,293	1,494.2
Proceeds from issuance of securities in securitization transaction	0	1,300
Repayments of notes payable, credit facilities, senior notes, secured debt, term loans and finance leases	(3,568.4)	(4,897.9)
Distributions to noncontrolling interest holders	(160.6)	(11.2)
Contributions from noncontrolling interest holders	101.4	0
Proceeds from stock options	13.9	1.8
Distributions paid on common stock	(802.1)	(733.6)
Deferred financing costs and other financing activities	(66.6)	(65)
Cash used for financing activities	(390.2)	(1,012.6)
Net effect of changes in foreign currency exchange rates on cash and cash equivalents, and restricted cash	(34)	3.6
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS, AND RESTRICTED CASH	423.3	(215.3)
CASH AND CASH EQUIVALENTS, AND RESTRICTED CASH, BEGINNING OF PERIOD	2,093.4	2,140.7
CASH AND CASH EQUIVALENTS, AND RESTRICTED CASH, END OF PERIOD	2,516.7	1,925.4
CASH PAID FOR INCOME TAXES (NET OF REFUNDS OF $3.4 AND $8.4, RESPECTIVELY)	66.5	62.3
CASH PAID FOR INTEREST	442.3	388.9
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Purchases of property and equipment under finance leases and perpetual easements	3.6	7.3
Decrease in accounts payable and accrued expenses for purchases of property and equipment and construction activities	(54.6)	(71.7)
Distributions to noncontrolling interest holders	(37.5)	0
Contributions from noncontrolling interest holders	$ 37.5	$ 0

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Cash Flows [Abstract]
Income tax refunds	$ 3.4	$ 8.4

CONSOLIDATED STATEMENTS OF EQUI

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Distributions in Excess of Earnings	Noncontrolling Interests
Balance at beginning of period, common stock (in shares) at Dec. 31, 2022		476,623
Balance at beginning of period at Dec. 31, 2022	$ 12,408.5	$ 4.8	$ (1,301.2)	$ 14,689	$ (5,718.3)	$ (2,101.9)	$ 6,836.1
Balance at beginning of period, treasury stock (in shares) at Dec. 31, 2022			(11,004)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation related activity (in shares)		419
Stock-based compensation related activity	36.6	$ 0		36.6
Foreign currency translation adjustment, net of tax	232.1				192.2		39.9
Distributions to noncontrolling interest holders	(11.5)						(11.5)
Common stock distributions declared	(730.4)					(730.4)
Net income (loss)	315					335.8	(20.8)
Balance at end of period, common stock (in shares) at Mar. 31, 2023		477,042
Balance at end of period at Mar. 31, 2023	$ 12,250.3	$ 4.8	$ (1,301.2)	14,725.6	(5,526.1)	(2,496.5)	6,843.7
Balance at end of period, treasury stock (in shares) at Mar. 31, 2023			(11,004)
Balance at beginning of period, common stock (in shares) at Dec. 31, 2023	466,296	477,300
Balance at beginning of period at Dec. 31, 2023	$ 10,865.4	$ 4.8	$ (1,301.2)	14,872.9	(5,739.5)	(3,638.8)	6,667.2
Balance at beginning of period, treasury stock (in shares) at Dec. 31, 2023	(11,004)		(11,004)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation related activity (in shares)		668
Stock-based compensation related activity	$ 30.5	$ 0		30.5
Foreign currency translation adjustment, net of tax	(431.2)				(338.5)		(92.7)
Contributions from noncontrolling interest holders	138.9						138.9
Distributions to noncontrolling interest holders	(103.8)						(103.8)
Common stock distributions declared	(759.8)					(759.8)
Net income (loss)	$ 921.7					917.4	4.3
Balance at end of period, common stock (in shares) at Mar. 31, 2024	466,964	477,968
Balance at end of period at Mar. 31, 2024	$ 10,661.7	$ 4.8	$ (1,301.2)	$ 14,903.4	$ (6,078)	$ (3,481.2)	$ 6,613.9
Balance at end of period, treasury stock (in shares) at Mar. 31, 2024	(11,004)		(11,004)

BASIS OF PRESENTATION AND SIGNI

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES The accompanying consolidated and condensed consolidated financial statements have been prepared by American Tower Corporation (together with its subsidiaries, “ATC” or the “Company”) pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The financial information included herein is unaudited. However, the Company believes that all adjustments, which are of a normal and recurring nature, 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, 2023 (the “2023 Form 10-K”). The results of operations for the three months ended March 31, 2024 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 method or as investments in equity securities, 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 March 31, 2024, the Company holds (i) a 52% controlling interest in subsidiaries whose holdings consist of the Company’s operations in France, Germany and Spain (such subsidiaries collectively, “ATC Europe”) (Allianz and CDPQ (each as defined in note 11) hold the noncontrolling interests), (ii) a 51% controlling interest in a joint venture whose holdings consist of the Company’s operations in Bangladesh (Confidence Tower Holdings Ltd. (“Confidence Group”) holds the noncontrolling interest) and (iii) a controlling common equity interest of approximately 72% in the Company’s U.S. data center business (Stonepeak (as defined and further discussed in note 11) holds approximately 28% of the outstanding common equity and 100% of the outstanding mandatorily convertible preferred equity). As of March 31, 2024, ATC Europe holds an 87% and an 83% controlling interest in subsidiaries that consist of the Company’s operations in Germany and Spain, respectively (PGGM holds the noncontrolling interests). See note 11 for a discussion of changes to the Company’s noncontrolling interests during the three months ended March 31, 2024 and 2023. Pending ATC TIPL Transaction— On January 4, 2024, the Company, through its subsidiaries, ATC Asia Pacific Pte. Ltd. and ATC Telecom Infrastructure Private Limited (“ATC TIPL”), entered into an agreement with Data Infrastructure Trust (“DIT”), an infrastructure investment trust sponsored by an affiliate of Brookfield Asset Management, pursuant to which DIT will acquire a 100% ownership interest in ATC TIPL (the “Pending ATC TIPL Transaction”). Subject to certain pre-closing terms, total aggregate consideration would potentially represent up to approximately 210 billion Indian Rupees (“INR”) (approximately $2.5 billion), including the value of the VIL OCDs and the VIL Shares (each as defined and further discussed in note 7), payments on certain existing customer receivables, the repayment of existing intercompany debt and the repayment, or assumption, of the Company’s existing term loan in India, by DIT. During the three months ended March 31, 2024, ATC TIPL distributed approximately 9,603 million INR (approximately $115.1 million) to the Company, which will be deducted from the total aggregate consideration received at closing. The Company will retain the full economic benefit associated with the VIL OCDs, the VIL Shares and rights to payments on certain existing customer receivables. The Pending ATC TIPL Transaction is expected to close in the second half of 2024, subject to customary closing conditions, including government and regulatory approval. Reportable Segments —The Company reports its results in seven segments – U.S. & Canada property, Asia-Pacific property, Africa property, Europe property, Latin America property, Data Centers and Services, which are discussed further in note 14. Significant Accounting Policies —The Company’s significant accounting policies are described in note 1 to the Company’s consolidated financial statements included in the 2023 Form 10-K. There have been no material changes to the Company’s significant accounting policies during the three months ended March 31, 2024, other than those noted below. Property and Equipment —The Company finalized its review of the estimated useful lives of its tower assets during the three months ended March 31, 2024. The Company now has over 20 years of operating history, and determined that it should modify its current estimates for asset lives based on its historical operating experience. The Company retained an independent consultant to assist the Company in completing this review and analysis. The Company previously depreciated its towers on a straight-line basis over the shorter of the term of the underlying ground lease (including renewal options) taking into account residual value or the estimated useful life of the tower, which the Company had historically estimated to be 20 years. The Company determined that the estimated useful life of its tower assets is 30 years, before taking into account residual value. Additionally, certain of the Company’s intangible assets are amortized on a similar basis to its tower assets, as the estimated useful lives of such intangible assets correlate to the useful life of the towers. The Company accounted for the changes in the useful lives as a change in accounting estimate under ASC 250 Accounting Changes and Error Corrections, which will be recorded prospectively beginning on January 1, 2024. On January 1, 2024, the Company began depreciating its towers and related intangible assets on a straight-line basis over the remaining estimated useful life of the tower, taking into account the extended useful life and residual value. The extension of the asset lives (i) resulted in an approximately $515 million increase in the right of use asset, as additional renewal options may be included, with an offsetting adjustment made to increase the related operating lease liability and (ii) is expected to result in an estimated $730 million decrease in depreciation and amortization expense for the year ended December 31, 2024. Asset Retirement Obligations —The Company finalized its review of the estimated settlement dates for its asset retirement obligations during the three months ended March 31, 2024. The Company now has over 20 years of operating history, and determined that it should modify its current estimated settlement dates based on its historical operating experience, management’s intent with respect to the assets, and the assets’ estimated useful lives. Based on its review and analysis, the Company concluded that a revision in the estimated settlement dates for its asset retirement obligations was appropriate. The Company accounted for the change in estimated settlement dates as a change in accounting estimate under ASC 250 Accounting Changes and Error Corrections, which will be recorded prospectively beginning on January 1, 2024. The extension in the estimated settlement dates (i) resulted in a $470 million increase in the asset retirement obligation liability, with an offsetting adjustment made to the related long-lived tangible asset and an $875 million increase in the estimated undiscounted future cash outlay for asset retirement obligations, and (ii) is expected to result in an estimated $75 million decrease in accretion expense for the year ended December 31, 2024. Adoption of Highly Inflationary Accounting in Ghana— The Ghanaian economy was deemed to be highly inflationary and, as a result, the Company adopted highly inflationary accounting as of January 1, 2024 for its subsidiary in Ghana. Under highly inflationary accounting, the functional currency of its subsidiary in Ghana will become the U.S. Dollar. All monetary and non-monetary assets and liabilities will be remeasured at the U.S. Dollar to Ghanaian Cedis exchange rate of 1 to 11.95 as of December 31, 2023. These amounts will become the new basis for those assets and liabilities as of January 1, 2024. Non-monetary assets and liabilities, as well as the corresponding income statement activities such as depreciation, amortization and equity, will continue to be measured at the historical exchange rate on December 31, 2023. Gains and losses on foreign currency arising in connection with the remeasurement of local currency denominated monetary assets and liabilities for foreign operating subsidiaries in economies that are deemed to be highly inflationary are reflected in Other expense in the consolidated statements of operations. This change is not expected to have a material impact on the Company’s financial statements, as Ghana’s assets and revenue are approximately 1% and 1% of consolidated assets and revenue, respectively. Cash and Cash Equivalents and Restricted Cash —The reconciliation of cash and cash equivalents and restricted cash reported within the applicable balance sheet that sum to the total of the same such amounts shown in the statements of cash flows is as follows: Three Months Ended March 31, 2024 2023 Cash and cash equivalents $ 2,389.1 $ 1,803.0 Restricted cash 127.6 122.4 Total cash, cash equivalents and restricted cash $ 2,516.7 $ 1,925.4 Revenue —The Company’s revenue is derived from leasing the right to use its communications sites, the land on which the sites are located, the land underlying its customers’ sites and the space in its data center facilities (the “lease component”) and from the reimbursement of costs incurred by the Company in operating the communications sites and data center facilities and supporting its customers’ equipment as well as other services and contractual rights (the “non-lease component”). Most of the Company’s revenue is derived from leasing arrangements and is accounted for as lease revenue unless the timing and pattern of revenue recognition of the non-lease component differs from the lease component. If the timing and pattern of the non-lease component revenue recognition differs from that of the lease component, the Company separately determines the stand-alone selling prices and pattern of revenue recognition for each performance obligation. Revenue related to distributed antenna system (“DAS”) networks and fiber and other related assets results from agreements with customers that are generally not accounted for as leases. Non-lease property revenue —Non-lease property revenue consists primarily of revenue generated from DAS networks, fiber and other property related revenue. DAS networks and fiber arrangements generally require that the Company provide the tenant the right to use available capacity on the applicable communications infrastructure. Performance obligations are satisfied over time for the duration of the arrangements. Non-lease property revenue also includes revenue generated from interconnection offerings in the Company’s data center facilities. Interconnection offerings are generally contracted on a month-to-month basis and are cancellable by the Company or the data center customer at any time. Performance obligations are satisfied over time for the duration of the arrangements. Other property related revenue streams, which include site inspections, are not material on either an individual or consolidated basis. There were no material changes in the receivables, contract assets and contract liabilities from contracts with customers for the three months ended March 31, 2024. Services revenue —The Company offers tower-related services in the United States. These services include site application, zoning and permitting (“AZP”), structural and mount analyses, and construction management. There is a single performance obligation related to AZP and construction management, and revenue is recognized over time based on milestones achieved, which are determined based on costs expected to be incurred. Structural and mount analyses services may have more than one performance obligation, contingent upon the number of contracted services. Revenue is recognized at the point in time the services are completed. A summary of revenue disaggregated by source and geography is as follows: Three Months Ended March 31, 2024 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Total Non-lease property revenue $ 72.9 $ 2.2 $ 6.1 $ 3.5 $ 28.7 $ 31.6 $ 145.0 Services revenue 30.2 — — — — — 30.2 Total non-lease revenue $ 103.1 $ 2.2 $ 6.1 $ 3.5 $ 28.7 $ 31.6 $ 175.2 Property lease revenue 1,237.8 324.4 285.9 201.0 416.8 193.0 2,658.9 Total revenue $ 1,340.9 $ 326.6 $ 292.0 $ 204.5 $ 445.5 $ 224.6 $ 2,834.1 Three Months Ended March 31, 2023 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Total Non-lease property revenue $ 71.0 $ 2.3 $ 6.7 $ 3.4 $ 41.3 $ 28.3 $ 153.0 Services revenue 52.7 — — — — — 52.7 Total non-lease revenue $ 123.7 $ 2.3 $ 6.7 $ 3.4 $ 41.3 $ 28.3 $ 205.7 Property lease revenue 1,216.6 248.8 310.3 188.3 422.8 174.7 2,561.5 Total revenue $ 1,340.3 $ 251.1 $ 317.0 $ 191.7 $ 464.1 $ 203.0 $ 2,767.2 Property revenue for the three months ended March 31, 2024 and 2023 includes straight-line revenue of $79.0 million and $112.0 million, respectively. The Company actively monitors the creditworthiness of its customers. In recognizing customer revenue, the Company assesses the collectibility of both the amounts billed and the portion recognized in advance of billing on a straight-line basis. This assessment takes customer credit risk and business and industry conditions into consideration to ultimately determine the collectibility of the amounts billed. To the extent the amounts, based on management’s estimates, may not be collectible, revenue recognition is deferred until such point as collectibility is determined to be reasonably assured. During the three months ended March 31, 2023, the Company deferred recognition of revenue of approximately $33.0 million related to a customer in India. During the three months ended March 31, 2024, the Company recognized approximately $29.0 million of this previously deferred revenue. Accounting Standards Updates —In November 2023, the Financial Accounting Standards Board (“FASB”) issued guidance which is intended to improve reportable segment disclosure requirements, primarily through additional disclosures about significant segment expenses. The standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of this guidance on its consolidated financial statements and related disclosures. In December 2023, the FASB issued guidance which requires public entities to provide enhanced income tax disclosures on an annual basis. The new guidance requires an expanded rate reconciliation and the disaggregation of cash taxes paid by U.S. federal, U.S. state and foreign jurisdictions. The updated guidance is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the impact of this guidance on its consolidated financial statements and related disclosures. SEC Rule Changes — In March 2024, the SEC issued Final Rule No. 33-11275, “The Enhancement and Standardization of Climate-Related Disclosures for Investors.” If such rule remains in effect, the rule will require registrants to provide certain climate-related information in their registration statements and annual reports. The rule requires registrants to provide climate related disclosures, including, but not limited to, (i) material Scope 1 and Scope 2 greenhouse gas emissions, (ii) governance and oversight of material climate-related risks, (iii) the material impact of climate risks on the registrant’s strategy, business model and outlook, (iv) risk management processes for material climate-related risks and (v) material climate targets and goals. The rule also requires disclosure of (x) financial statement effects of severe weather events and other natural conditions, (y) carbon offset and renewable energy credit information and (z) the impact of severe weather events and other natural conditions on estimates and assumptions. Disclosure requirements will begin phasing in for fiscal years beginning on or after January 1, 2025. In April 2024, the SEC issued an order staying implementation of such rule pending the resolution of certain challenges. The outcome of ongoing litigation is currently unknown. The Company is currently evaluating the potential impact of such rule on its consolidated financial statements and disclosures.

PREPAID AND OTHER CURRENT ASSET

PREPAID AND OTHER CURRENT ASSETS	3 Months Ended
	Mar. 31, 2024
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: As of March 31, 2024 December 31, 2023 Prepaid assets $ 98.9 $ 93.4 Prepaid income tax 127.3 102.9 Unbilled receivables 383.9 323.2 Value added tax and other consumption tax receivables 57.9 79.8 Other miscellaneous current assets (1) 316.6 347.6 Prepaid and other current assets $ 984.6 $ 946.9 _______________ (1) Includes the VIL OCDs and the VIL Shares (each as defined and further discussed in note 7).

LEASES

LEASES	3 Months Ended
	Mar. 31, 2024
Leases [Abstract]
LEASES	LEASES The Company determines if an arrangement is a lease at the inception of the agreement. The Company considers an arrangement to be a lease if it conveys the right to control the use of the communications infrastructure or ground space underneath communications infrastructure for a period of time in exchange for consideration. The Company is both a lessor and a lessee. During the three months ended March 31, 2024, the Company made no changes to the methods described in note 4 to its consolidated financial statements included in the 2023 Form 10-K. As of March 31, 2024, the Company does not have any material related party leases as either a lessor or a lessee. To the extent there are any intercompany leases, these are eliminated in consolidation. If incentives are present in the Company’s leases, they are evaluated to determine proper treatment and, to the extent present, are recorded in Other current assets and Other non-current assets in the consolidated balance sheets and amortized on a straight line basis over the corresponding lease term as a non-cash reduction to revenue. As of March 31, 2024, the remaining weighted average amortization period of the Company’s lease incentives was 10 years. As of March 31, 2024, Other current assets and Other non-current assets include $35.5 million and $339.4 million, respectively, for lease incentives. Lessor — Historically, the Company has been able to successfully renew its applicable leases as needed to ensure continuation of its revenue. Accordingly, the Company assumes that it will have access to the communications infrastructure or ground space underlying its sites when calculating future minimum rental receipts through the end of the respective terms. Future minimum rental receipts expected under non-cancellable operating lease agreements as of March 31, 2024 were as follows: Fiscal Year Amount (1) (2) Remainder of 2024 $ 6,292.1 2025 7,870.7 2026 7,385.8 2027 7,173.0 2028 5,857.2 Thereafter 25,221.6 Total $ 59,800.4 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods. (2) Balances represent contractual amounts owed with no adjustments made for expected collectibility. Lessee —The Company assesses its right-of-use asset and other lease-related assets for impairment, as described in note 1 to the Company’s consolidated financial statements included in the 2023 Form 10-K. There were no material impairments recorded related to these assets during the three months ended March 31, 2024 and 2023. The Company leases certain land, buildings, equipment and office space under operating leases and land and improvements, towers, equipment and vehicles under finance leases. As of March 31, 2024, operating lease assets were included in Right-of-use asset and finance lease assets were included in Property and equipment, net in the consolidated balance sheet. During the three months ended March 31, 2024, other than leases acquired in connection with acquisitions, there were no material changes in the terms and provisions of the Company’s operating leases in which the Company is a lessee, other than those related to the change in estimated useful lives as described in note 1. As a result of the change in estimated useful lives of its assets, the Company reviewed its lease portfolio to determine whether additional renewal options were likely to be exercised. The Company concluded that these incremental renewals were lease modifications and has accounted for them accordingly. The extension of the asset lives resulted in an approximately $515 million increase in the right of use asset, as additional renewal options may be included, with an offsetting adjustment made to increase the related operating lease liability. There were no material changes in finance lease assets and liabilities during the three months ended March 31, 2024. Information about other lease-related balances is as follows: As of March 31, 2024 December 31, 2023 Operating leases: Right-of-use asset $ 9,199.8 $ 8,878.8 Current portion of lease liability $ 715.2 $ 794.6 Lease liability 7,866.3 7,438.7 Total operating lease liability $ 8,581.5 $ 8,233.3 The weighted-average remaining lease terms and incremental borrowing rates are as follows: As of March 31, 2024 December 31, 2023 Operating leases: Weighted-average remaining lease term (years) (1) 13.7 11.6 Weighted-average incremental borrowing rate 6.7 % 5.8 % ______________ (1) As of March 31, 2024, reflects the change in estimated useful lives as described in note 1. The following table sets forth the components of lease cost: Three Months Ended March 31, 2024 2023 Operating lease cost $ 326.4 $ 306.7 Variable lease costs not included in lease liability (1) 89.2 109.1 ______________ (1) Primarily includes property tax paid on behalf of the landlord. Supplemental cash flow information is as follows: Three Months Ended March 31, 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (365.9) $ (342.6) Non-cash items: New operating leases (1) $ 39.1 $ 56.5 Operating lease modifications and reassessments (2) $ 593.9 $ 102.9 ______________ (1) Amount includes new operating leases and leases acquired in connection with acquisitions. (2) For the three months ended March 31, 2024, reflects the change in estimated useful lives as described in note 1. As of March 31, 2024, the Company does not have material operating or financing leases that have not yet commenced. Maturities of operating lease liabilities as of March 31, 2024 were as follows: Fiscal Year Operating Lease (1) Remainder of 2024 $ 880.2 2025 1,116.3 2026 1,062.8 2027 1,003.8 2028 943.0 Thereafter 8,346.5 Total lease payments 13,352.6 Less amounts representing interest (4,771.1) Total lease liability 8,581.5 Less current portion of lease liability 715.2 Non-current lease liability $ 7,866.3 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods.
LEASES	LEASES The Company determines if an arrangement is a lease at the inception of the agreement. The Company considers an arrangement to be a lease if it conveys the right to control the use of the communications infrastructure or ground space underneath communications infrastructure for a period of time in exchange for consideration. The Company is both a lessor and a lessee. During the three months ended March 31, 2024, the Company made no changes to the methods described in note 4 to its consolidated financial statements included in the 2023 Form 10-K. As of March 31, 2024, the Company does not have any material related party leases as either a lessor or a lessee. To the extent there are any intercompany leases, these are eliminated in consolidation. If incentives are present in the Company’s leases, they are evaluated to determine proper treatment and, to the extent present, are recorded in Other current assets and Other non-current assets in the consolidated balance sheets and amortized on a straight line basis over the corresponding lease term as a non-cash reduction to revenue. As of March 31, 2024, the remaining weighted average amortization period of the Company’s lease incentives was 10 years. As of March 31, 2024, Other current assets and Other non-current assets include $35.5 million and $339.4 million, respectively, for lease incentives. Lessor — Historically, the Company has been able to successfully renew its applicable leases as needed to ensure continuation of its revenue. Accordingly, the Company assumes that it will have access to the communications infrastructure or ground space underlying its sites when calculating future minimum rental receipts through the end of the respective terms. Future minimum rental receipts expected under non-cancellable operating lease agreements as of March 31, 2024 were as follows: Fiscal Year Amount (1) (2) Remainder of 2024 $ 6,292.1 2025 7,870.7 2026 7,385.8 2027 7,173.0 2028 5,857.2 Thereafter 25,221.6 Total $ 59,800.4 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods. (2) Balances represent contractual amounts owed with no adjustments made for expected collectibility. Lessee —The Company assesses its right-of-use asset and other lease-related assets for impairment, as described in note 1 to the Company’s consolidated financial statements included in the 2023 Form 10-K. There were no material impairments recorded related to these assets during the three months ended March 31, 2024 and 2023. The Company leases certain land, buildings, equipment and office space under operating leases and land and improvements, towers, equipment and vehicles under finance leases. As of March 31, 2024, operating lease assets were included in Right-of-use asset and finance lease assets were included in Property and equipment, net in the consolidated balance sheet. During the three months ended March 31, 2024, other than leases acquired in connection with acquisitions, there were no material changes in the terms and provisions of the Company’s operating leases in which the Company is a lessee, other than those related to the change in estimated useful lives as described in note 1. As a result of the change in estimated useful lives of its assets, the Company reviewed its lease portfolio to determine whether additional renewal options were likely to be exercised. The Company concluded that these incremental renewals were lease modifications and has accounted for them accordingly. The extension of the asset lives resulted in an approximately $515 million increase in the right of use asset, as additional renewal options may be included, with an offsetting adjustment made to increase the related operating lease liability. There were no material changes in finance lease assets and liabilities during the three months ended March 31, 2024. Information about other lease-related balances is as follows: As of March 31, 2024 December 31, 2023 Operating leases: Right-of-use asset $ 9,199.8 $ 8,878.8 Current portion of lease liability $ 715.2 $ 794.6 Lease liability 7,866.3 7,438.7 Total operating lease liability $ 8,581.5 $ 8,233.3 The weighted-average remaining lease terms and incremental borrowing rates are as follows: As of March 31, 2024 December 31, 2023 Operating leases: Weighted-average remaining lease term (years) (1) 13.7 11.6 Weighted-average incremental borrowing rate 6.7 % 5.8 % ______________ (1) As of March 31, 2024, reflects the change in estimated useful lives as described in note 1. The following table sets forth the components of lease cost: Three Months Ended March 31, 2024 2023 Operating lease cost $ 326.4 $ 306.7 Variable lease costs not included in lease liability (1) 89.2 109.1 ______________ (1) Primarily includes property tax paid on behalf of the landlord. Supplemental cash flow information is as follows: Three Months Ended March 31, 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (365.9) $ (342.6) Non-cash items: New operating leases (1) $ 39.1 $ 56.5 Operating lease modifications and reassessments (2) $ 593.9 $ 102.9 ______________ (1) Amount includes new operating leases and leases acquired in connection with acquisitions. (2) For the three months ended March 31, 2024, reflects the change in estimated useful lives as described in note 1. As of March 31, 2024, the Company does not have material operating or financing leases that have not yet commenced. Maturities of operating lease liabilities as of March 31, 2024 were as follows: Fiscal Year Operating Lease (1) Remainder of 2024 $ 880.2 2025 1,116.3 2026 1,062.8 2027 1,003.8 2028 943.0 Thereafter 8,346.5 Total lease payments 13,352.6 Less amounts representing interest (4,771.1) Total lease liability 8,581.5 Less current portion of lease liability 715.2 Non-current lease liability $ 7,866.3 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods.
LEASES	LEASES The Company determines if an arrangement is a lease at the inception of the agreement. The Company considers an arrangement to be a lease if it conveys the right to control the use of the communications infrastructure or ground space underneath communications infrastructure for a period of time in exchange for consideration. The Company is both a lessor and a lessee. During the three months ended March 31, 2024, the Company made no changes to the methods described in note 4 to its consolidated financial statements included in the 2023 Form 10-K. As of March 31, 2024, the Company does not have any material related party leases as either a lessor or a lessee. To the extent there are any intercompany leases, these are eliminated in consolidation. If incentives are present in the Company’s leases, they are evaluated to determine proper treatment and, to the extent present, are recorded in Other current assets and Other non-current assets in the consolidated balance sheets and amortized on a straight line basis over the corresponding lease term as a non-cash reduction to revenue. As of March 31, 2024, the remaining weighted average amortization period of the Company’s lease incentives was 10 years. As of March 31, 2024, Other current assets and Other non-current assets include $35.5 million and $339.4 million, respectively, for lease incentives. Lessor — Historically, the Company has been able to successfully renew its applicable leases as needed to ensure continuation of its revenue. Accordingly, the Company assumes that it will have access to the communications infrastructure or ground space underlying its sites when calculating future minimum rental receipts through the end of the respective terms. Future minimum rental receipts expected under non-cancellable operating lease agreements as of March 31, 2024 were as follows: Fiscal Year Amount (1) (2) Remainder of 2024 $ 6,292.1 2025 7,870.7 2026 7,385.8 2027 7,173.0 2028 5,857.2 Thereafter 25,221.6 Total $ 59,800.4 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods. (2) Balances represent contractual amounts owed with no adjustments made for expected collectibility. Lessee —The Company assesses its right-of-use asset and other lease-related assets for impairment, as described in note 1 to the Company’s consolidated financial statements included in the 2023 Form 10-K. There were no material impairments recorded related to these assets during the three months ended March 31, 2024 and 2023. The Company leases certain land, buildings, equipment and office space under operating leases and land and improvements, towers, equipment and vehicles under finance leases. As of March 31, 2024, operating lease assets were included in Right-of-use asset and finance lease assets were included in Property and equipment, net in the consolidated balance sheet. During the three months ended March 31, 2024, other than leases acquired in connection with acquisitions, there were no material changes in the terms and provisions of the Company’s operating leases in which the Company is a lessee, other than those related to the change in estimated useful lives as described in note 1. As a result of the change in estimated useful lives of its assets, the Company reviewed its lease portfolio to determine whether additional renewal options were likely to be exercised. The Company concluded that these incremental renewals were lease modifications and has accounted for them accordingly. The extension of the asset lives resulted in an approximately $515 million increase in the right of use asset, as additional renewal options may be included, with an offsetting adjustment made to increase the related operating lease liability. There were no material changes in finance lease assets and liabilities during the three months ended March 31, 2024. Information about other lease-related balances is as follows: As of March 31, 2024 December 31, 2023 Operating leases: Right-of-use asset $ 9,199.8 $ 8,878.8 Current portion of lease liability $ 715.2 $ 794.6 Lease liability 7,866.3 7,438.7 Total operating lease liability $ 8,581.5 $ 8,233.3 The weighted-average remaining lease terms and incremental borrowing rates are as follows: As of March 31, 2024 December 31, 2023 Operating leases: Weighted-average remaining lease term (years) (1) 13.7 11.6 Weighted-average incremental borrowing rate 6.7 % 5.8 % ______________ (1) As of March 31, 2024, reflects the change in estimated useful lives as described in note 1. The following table sets forth the components of lease cost: Three Months Ended March 31, 2024 2023 Operating lease cost $ 326.4 $ 306.7 Variable lease costs not included in lease liability (1) 89.2 109.1 ______________ (1) Primarily includes property tax paid on behalf of the landlord. Supplemental cash flow information is as follows: Three Months Ended March 31, 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (365.9) $ (342.6) Non-cash items: New operating leases (1) $ 39.1 $ 56.5 Operating lease modifications and reassessments (2) $ 593.9 $ 102.9 ______________ (1) Amount includes new operating leases and leases acquired in connection with acquisitions. (2) For the three months ended March 31, 2024, reflects the change in estimated useful lives as described in note 1. As of March 31, 2024, the Company does not have material operating or financing leases that have not yet commenced. Maturities of operating lease liabilities as of March 31, 2024 were as follows: Fiscal Year Operating Lease (1) Remainder of 2024 $ 880.2 2025 1,116.3 2026 1,062.8 2027 1,003.8 2028 943.0 Thereafter 8,346.5 Total lease payments 13,352.6 Less amounts representing interest (4,771.1) Total lease liability 8,581.5 Less current portion of lease liability 715.2 Non-current lease liability $ 7,866.3 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods.

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2024
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 each of the Company’s business segments were as follows: Property Services Total U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Balance as of January 1, 2024 $ 4,638.6 $ 562.7 $ 497.7 $ 3,051.9 $ 966.1 $ 2,920.0 $ 2.0 $ 12,639.0 Effect of foreign currency translation (1.1) (1.3) 1.6 (68.8) (12.6) — — (82.2) Balance as of March 31, 2024 $ 4,637.5 $ 561.4 $ 499.3 $ 2,983.1 $ 953.5 $ 2,920.0 $ 2.0 $ 12,556.8 The Company’s other intangible assets subject to amortization consisted of the following: As of March 31, 2024 As of December 31, 2023 Estimated Useful Gross Accumulated Net Book Gross Accumulated Net Book Acquired network location intangibles (2) Up to 30 $ 5,930.6 $ (2,795.5) $ 3,135.1 $ 5,981.5 $ (2,775.8) $ 3,205.7 Acquired tenant-related intangibles Up to 30 18,728.8 (6,815.0) 11,913.8 18,894.5 (6,698.6) 12,195.9 Acquired licenses and other intangibles 2-30 1,535.5 (465.1) 1,070.4 1,561.1 (442.0) 1,119.1 Total other intangible assets $ 26,194.9 $ (10,075.6) $ 16,119.3 $ 26,437.1 $ (9,916.4) $ 16,520.7 _______________ (1) As of March 31, 2024, reflects the change in estimated useful lives as described in note 1. (2) Beginning January 1, 2024, acquired network location intangibles are amortized over the remaining estimated useful life of the tower, taking into account residual value, generally up to 30 years, as the Company considers these intangibles to be directly related to the tower assets. Prior to January 1, 2024, acquired network location intangibles were amortized over the shorter of the term of the corresponding ground lease, taking into consideration lease renewal options and residual value, or the estimated useful life of the tower, generally up to 20 years. 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 tower communications infrastructure. The acquired tenant-related intangibles typically represent the value to the Company of tenant contracts and relationships in place at the time of an acquisition or similar transaction, including assumptions regarding estimated renewals. Other intangibles represent the value of acquired licenses, trade name and in place leases. In place lease value represents the fair value of costs avoided in securing data center customers, including vacancy periods, legal costs and commissions. In place lease value also includes assumptions on similar costs avoided upon the renewal or extension of existing leases on a basis consistent with occupancy assumptions used in the fair value of other assets. The Company amortizes its acquired intangible assets on a straight-line basis over their estimated useful lives. As of March 31, 2024, the remaining weighted average amortization period of the Company’s intangible assets was 20 years. Amortization of intangible assets for the three months ended March 31, 2024 and 2023 was $242.5 million and $369.5 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: Fiscal Year Amount (1) Remainder of 2024 $ 707.8 2025 921.9 2026 881.5 2027 869.5 2028 858.0 2029 839.0 ______________ (1)

ACCRUED EXPENSES

ACCRUED EXPENSES	3 Months Ended
	Mar. 31, 2024
Accrued Liabilities, Current [Abstract]
ACCRUED EXPENSES	ACCRUED EXPENSES Accrued expenses consisted of the following: As of March 31, 2024 December 31, 2023 Accrued construction costs $ 131.9 $ 183.8 Accrued income tax payable 26.9 21.0 Accrued pass-through costs 97.0 77.4 Amounts payable for acquisitions 1.9 27.7 Amounts payable to tenants 99.5 103.3 Accrued property and real estate taxes 294.5 295.5 Accrued rent 75.6 75.1 Payroll and related withholdings 98.2 147.4 Other accrued expenses 308.6 349.4 Total accrued expenses $ 1,134.1 $ 1,280.6

LONG-TERM OBLIGATIONS

LONG-TERM OBLIGATIONS	3 Months Ended
	Mar. 31, 2024
Debt Disclosure [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: As of March 31, 2024 December 31, 2023 Maturity Date 2021 Multicurrency Credit Facility (1) (2) $ 1,011.6 $ 723.4 July 1, 2026 2021 Term Loan (1) 997.2 997.0 January 31, 2027 2021 Credit Facility (1) 2,038.4 1,603.4 July 1, 2028 2021 EUR Three Year Delayed Draw Term Loan (1) (2) 890.1 910.7 May 28, 2024 0.600% senior notes (3) — 500.0 N/A 5.00% senior notes (4) — 1,000.1 N/A 3.375% senior notes 650.0 649.7 May 15, 2024 2.950% senior notes 648.6 648.2 January 15, 2025 2.400% senior notes 748.8 748.5 March 15, 2025 1.375% senior notes (5) 538.0 550.0 April 4, 2025 4.000% senior notes 748.4 748.1 June 1, 2025 1.300% senior notes 498.5 498.3 September 15, 2025 4.400% senior notes 498.9 498.7 February 15, 2026 1.600% senior notes 697.7 697.4 April 15, 2026 1.950% senior notes (5) 537.4 549.6 May 22, 2026 1.450% senior notes 596.3 595.9 September 15, 2026 3.375% senior notes 995.1 994.7 October 15, 2026 3.125% senior notes 399.0 398.9 January 15, 2027 2.750% senior notes 747.3 747.0 January 15, 2027 0.450% senior notes (5) 805.9 824.3 January 15, 2027 0.400% senior notes (5) 536.1 548.2 February 15, 2027 3.650% senior notes 645.2 644.8 March 15, 2027 4.125% senior notes (5) 643.9 658.6 May 16, 2027 3.55% senior notes 747.3 747.1 July 15, 2027 3.600% senior notes 696.3 696.0 January 15, 2028 0.500% senior notes (5) 804.4 822.8 January 15, 2028 1.500% senior notes 647.3 647.1 January 31, 2028 5.500% senior notes 694.0 693.6 March 15, 2028 5.250% senior notes 644.2 643.9 July 15, 2028 5.800% senior notes 743.7 743.4 November 15, 2028 5.200% senior notes 642.7 — February 15, 2029 3.950% senior notes 594.0 593.7 March 15, 2029 0.875% senior notes (5) 805.1 823.7 May 21, 2029 3.800% senior notes 1,639.1 1,638.6 August 15, 2029 2.900% senior notes 744.5 744.2 January 15, 2030 2.100% senior notes 743.4 743.1 June 15, 2030 0.950% senior notes (5) 533.8 546.0 October 5, 2030 1.875% senior notes 793.6 793.3 October 15, 2030 2.700% senior notes 695.2 695.0 April 15, 2031 4.625% senior notes (5) 533.0 545.2 May 16, 2031 2.300% senior notes 692.9 692.7 September 15, 2031 1.000% senior notes (5) 695.4 711.5 January 15, 2032 4.050% senior notes 643.1 642.9 March 15, 2032 5.650% senior notes 790.8 790.6 March 15, 2033 1.250% senior notes (5) 533.4 545.8 May 21, 2033 5.550% senior notes 840.8 840.6 July 15, 2033 5.900% senior notes 741.7 741.5 November 15, 2033 5.450% senior notes 640.0 — February 15, 2034 3.700% senior notes 592.5 592.4 October 15, 2049 3.100% senior notes 1,038.6 1,038.6 June 15, 2050 2.950% senior notes 1,023.3 1,023.2 January 15, 2051 Total American Tower Corporation debt 36,806.5 36,472.0 Series 2015-2 notes (6) 524.2 524.1 June 16, 2025 Series 2018-1A securities (7) 497.0 496.8 March 15, 2028 Series 2023-1A securities (8) 1,285.3 1,284.4 March 15, 2028 Other subsidiary debt (9) 126.7 123.6 Various Total American Tower subsidiary debt 2,433.2 2,428.9 Finance lease obligations 19.8 20.6 Total 39,259.5 38,921.5 Less current portion of long-term obligations (3,067.6) (3,187.5) Long-term obligations $ 36,191.9 $ 35,734.0 _______________ (1) Accrues interest at a variable rate. (2) Reflects borrowings denominated in Euro (“EUR”) and, for the 2021 Multicurrency Credit Facility (as defined below), reflects borrowings denominated in both EUR and U.S. Dollars (“USD”). (3) Repaid in full on January 12, 2024 using borrowings under the 2021 Multicurrency Credit Facility. (4) Repaid in full on February 14, 2024 using borrowings under the 2021 Multicurrency Credit Facility. (5) Notes are denominated in EUR. (6) Maturity date reflects the anticipated repayment date; final legal maturity is June 15, 2050. (7) Maturity date reflects the anticipated repayment date; final legal maturity is March 15, 2048. (8) Maturity date reflects the anticipated repayment date; final legal maturity is March 15, 2053. (9) Includes amounts drawn under letters of credit in Nigeria, which are denominated in USD, and borrowings under an unsecured term loan in India (the “India Term Loan”), which is denominated in INR. In January 2024, the Company amended the India Term Loan to extend the maturity date to December 31, 2024. Current portion of long-term obligations— The Company’s current portion of long-term obligations primarily includes (i) $650.0 million aggregate principal amount of the Company’s 3.375% senior unsecured notes due May 15, 2024, (ii) $650.0 million aggregate principal amount of the Company’s 2.950% senior unsecured notes due January 15, 2025, (iii) $750.0 million aggregate principal amount of the Company’s 2.400% senior unsecured notes due March 15, 2025 and (iv) 825.0 million EUR in borrowings under the 2021 EUR Three Year Delayed Draw Term Loan (as defined below). Securitized Debt— Cash flows generated by the communications sites that secure the securitized debt of the Company are only available for payment of such debt and are not available to pay the Company’s other obligations or the claims of its creditors. However, subject to certain restrictions, the Company holds the right to receive the excess cash flows not needed to service the securitized debt and other obligations arising out of the securitizations. The securitized debt is the obligation of the issuers thereof or borrowers thereunder, as applicable, and their subsidiaries, and not of the Company or its other subsidiaries. Repayments of Senior Notes Repayment of 0.600% Senior Notes —On January 12, 2024, the Company repaid $500.0 million aggregate principal amount of the Company’s 0.600% senior unsecured notes due 2024 (the “0.600% Notes”) upon their maturity. The 0.600% Notes were repaid using borrowings under the 2021 Multicurrency Credit Facility. Upon completion of the repayment, none of the 0.600% Notes remained outstanding. Repayment of 5.00% Senior Notes —On February 14, 2024, the Company repaid $1.0 billion aggregate principal amount of the Company’s 5.00% senior unsecured notes due 2024 (the “5.00% Notes”) upon their maturity. The 5.00% Notes were repaid using borrowings under the 2021 Multicurrency Credit Facility. Upon completion of the repayment, none of the 5.00% Notes remained outstanding. Offerings of Senior Notes 5.200% Senior Notes and 5.450% Senior Notes Offering— On March 7, 2024, the Company completed a registered public offering of $650.0 million aggregate principal amount of 5.200% senior unsecured notes due 2029 (the “5.200% Notes”) and $650.0 million aggregate principal amount of 5.450% senior unsecured notes due 2034 (the “5.450% Notes” and, together with the 5.200% Notes, the “Notes”). The net proceeds from this offering were approximately $1,281.3 million, after deducting commissions and estimated expenses. The Company used the net proceeds to repay existing indebtedness under the 2021 Multicurrency Credit Facility. The key terms of the Notes are as follows: Senior Notes Aggregate Principal Amount (in millions) Issue Date and Interest Accrual Date Maturity Date Contractual Interest Rate First Interest Payment Interest Payments Due (1) Par Call Date (2) 5.200% Notes $ 650.0 March 7, 2024 February 15, 2029 5.200% August 15, 2024 February 15 and August 15 January 15, 2029 5.450% Notes $ 650.0 March 7, 2024 February 15, 2034 5.450% August 15, 2024 February 15 and August 15 November 15, 2033 ___________ (1) Accrued and unpaid interest on USD denominated notes is payable in USD semi-annually in arrears and will be computed from the issue date on the basis of a 360-day year comprised of twelve 30-day months. (2) The Company may redeem the 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 Notes on or after the par call date, the Company will not be required to pay a make-whole premium. If the Company undergoes a change of control and corresponding ratings decline, each as defined in the supplemental indenture for the Notes, the Company may be required to repurchase all of the Notes at a purchase price equal to 101% of the aggregate principal amount of the Notes repurchased, plus accrued and unpaid interest (including additional interest, if any), up to but not including the repurchase date. The Notes rank equally in right of payment with all of the Company’s other senior unsecured debt obligations and are structurally subordinated to all existing and future indebtedness and other obligations of its subsidiaries. The supplemental indenture contains certain covenants that restrict the Company’s ability to merge, consolidate or sell assets and its (together with its subsidiaries’) ability to incur liens. These covenants are subject to a number of exceptions, including that the Company and its subsidiaries may incur certain liens on assets, mortgages or other liens securing indebtedness if the aggregate amount of indebtedness secured by such liens does not exceed 3.5x Adjusted EBITDA, as defined in the supplemental indenture. Bank Facilities 2021 Multicurrency Credit Facility— During the three months ended March 31, 2024, the Company borrowed an aggregate of $2.0 billion, including 315.0 million EUR ($339.4 million as of the borrowing date) and repaid an aggregate of $1.7 billion, including 85.0 million EUR ($91.9 million as of the repayment date), of revolving indebtedness under the Company’s $6.0 billion senior unsecured multicurrency revolving credit facility, as amended and restated in December 2021, as further amended (the “2021 Multicurrency Credit Facility”). The Company used the borrowings to repay outstanding indebtedness, including the 0.600% Notes and the 5.00% Notes, and for general corporate purposes. 2021 Credit Facility— During the three months ended March 31, 2024, the Company borrowed an aggregate of $775.0 million and repaid an aggregate of $340.0 million of revolving indebtedness under the Company’s $4.0 billion senior unsecured revolving credit facility, as amended and restated in December 2021, as further amended (the “2021 Credit Facility”). The Company used the borrowings for general corporate purposes. As of March 31, 2024, the key terms under the 2021 Multicurrency Credit Facility, the 2021 Credit Facility, the Company’s $1.0 billion unsecured term loan, as amended and restated in December 2021, as further amended (the “2021 Term Loan”) and the Company’s 825.0 million EUR unsecured term loan, as amended in December 2021 (the “2021 EUR Three Year Delayed Draw Term Loan”) were as follows: Outstanding Principal Balance Undrawn letters of credit Maturity Date Current margin over SOFR or EURIBOR (1) Current commitment fee (2) 2021 Multicurrency Credit Facility $ 1,011.6 $ 3.5 July 1, 2026 (3) 1.125 % 0.110 % 2021 Credit Facility 2,038.4 30.4 July 1, 2028 (3) 1.125 % 0.110 % 2021 Term Loan 1,000.0 N/A January 31, 2027 1.125 % N/A 2021 EUR Three Year Delayed Draw Term Loan 890.2 N/A May 28, 2024 1.125 % N/A _______________ (1) SOFR applies to the USD denominated borrowings under the 2021 Multicurrency Credit Facility, the 2021 Credit Facility and the 2021 Term Loan. Euro Interbank Offer Rate (“EURIBOR”) applies to the EUR denominated borrowings under the 2021 Multicurrency Credit Facility and all of the borrowings under the 2021 EUR Three Year Delayed Draw Term Loan. (2) Fee on undrawn portion of each credit facility. (3)

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2024
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: March 31, 2024 December 31, 2023 Fair Value Measurements Using Fair Value Measurements Using Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets: Investments in equity securities (1) $ 13.5 $ 5.3 — $ 28.2 $ 5.3 — VIL Shares — $ 172.7 — — — — VIL OCDs — $ 19.2 — — $ 192.3 — _______________ (1) Investments in equity securities are recorded in Notes receivable and other non-current assets in the consolidated balance sheet at fair value. Unrealized holding gains and losses for equity securities are recorded in Other income (expense) in the consolidated statements of operations in the current period. During the three months ended March 31, 2024 and 2023, the Company recognized unrealized (losses) gains of $(14.7) million and $1.2 million, respectively, for equity securities held as of March 31, 2024. VIL Optionally Convertible Debentures —In February 2023, and as amended in August 2023, one of the Company’s customers in India, Vodafone Idea Limited (“VIL”), issued optionally convertible debentures (the “VIL OCDs”) to the Company’s subsidiary, ATC TIPL, in exchange for VIL’s payment of certain amounts towards accounts receivables. The VIL OCDs are (a) to be repaid by VIL with interest or (b) convertible into equity of VIL. If converted and following registration, such equity shall be free to trade in the open market beginning on the one year anniversary of the date of issuance of the VIL OCDs. The VIL OCDs were issued for an aggregate face value of 16.0 billion INR (approximately $193.2 million on the date of issuance). The VIL OCDs were to mature in tranches with 8.0 billion INR (approximately $96.6 million on the date of issuance) maturing on August 27, 2023 and 8.0 billion INR (approximately $96.6 million on the date of issuance) maturing on August 27, 2024. In August 2023, the Company amended the agreements governing the VIL OCDs to, among other items, extend the maturity of the first tranche of the VIL OCDs to August 27, 2024. The fair value of the VIL OCDs at issuance was approximately $116.5 million. The VIL OCDs accrue interest at a rate of 11.2% annually. Interest is payable to ATC TIPL semi-annually, with the first payment received in September 2023. On March 23, 2024, the Company converted an aggregate face value of 14.4 billion INR (approximately $172.7 million) of VIL OCDs into 1,440 million shares of equity of VIL (the “VIL Shares”), which were unregistered as of March 31, 2024. The fair value of the VIL Shares as of March 31, 2024 was $172.7 million. The VIL Shares were registered on April 16, 2024 and the Company completed the sale of VIL Shares on April 29, 2024 for total net proceeds of approximately $216.0 million, as further discussed in note 15. The VIL OCDs and the VIL Shares are recorded in Prepaid and other current assets in the consolidated balance sheet at fair value. The significant input to the fair value of the VIL OCDs is the lesser of the (i) VIL equity share price underlying the instruments, less a liquidity discount, and (ii) redemption value. The significant input to the fair value of the VIL Shares is the VIL equity share price underlying the shares, less a liquidity discount. Unrealized holding gains and losses for the VIL OCDs are recorded in Other income (expense) in the consolidated statements of operations in the current period. 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. There were no material long-lived asset impairments during the three months ended March 31, 2024 or 2023 and there were no significant unobservable inputs used to determine the fair value of long-lived assets during the three months ended March 31, 2024 or 2023. Fair Value of Financial Instruments

INCOME TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [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. Under the provisions of the Internal Revenue Code of 1986, as amended, the Company may deduct earnings distributed to stockholders against the income generated by its real estate investment trust (“REIT”) operations. The Company continues to be subject to income taxes on the income of its domestic taxable REIT subsidiaries and income taxes in foreign jurisdictions where it conducts operations. 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 evidence to estimate if sufficient future taxable income will be generated to use the existing deferred tax assets. Valuation allowances may be reversed if, based on changes in facts and circumstances, the net deferred tax assets have been determined to be realizable. The increase in the income tax provision during the three months ended March 31, 2024 was primarily attributable to increased earnings in certain foreign jurisdictions, partially due to the impacts of the change in estimated useful lives on depreciation and amortization expense as described in note 1. As of March 31, 2024 and December 31, 2023, the total unrecognized tax benefits that would impact the ETR, if recognized, were approximately $132.1 million and $130.7 million, respectively. The amount of unrecognized tax benefits during the three months ended March 31, 2024 includes (i) additions to the Company’s existing tax positions of $1.0 million and (ii) changes due to foreign currency exchange rate fluctuations of $0.4 million. Unrecognized tax benefits are expected 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 2023 Form 10-K. The impact of the amount of these changes to previously recorded uncertain tax positions could range from zero to $14.3 million. The Company recorded the following penalties and income tax-related interest expense during the three months ended March 31, 2024 and 2023: Three Months Ended March 31, 2024 2023 Penalties and income tax-related interest expense $ 5.5 $ 2.8 As of March 31, 2024 and December 31, 2023, the total amount of accrued income tax related interest and penalties included in the consolidated balance sheets were $67.3 million and $62.8 million, respectively.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [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 Company’s 2007 Equity Incentive Plan, as amended (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 for 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. Awards granted prior to March 10, 2023 generally vest over four years for time-based restricted stock units (“RSUs”) and stock options. In December 2022, the Company’s Compensation Committee changed the terms of its awards to generally vest over three years. The change in vesting terms is applicable for new awards granted beginning on March 10, 2023 and does not change the vesting terms applicable to grants awarded prior to March 10, 2023. Performance-based restricted stock units (“PSUs”) generally vest over three years. Stock options generally expire ten years from the date of grant. As of March 31, 2024, the Company had the ability to grant stock-based awards with respect to an aggregate of 3.3 million shares of common stock under the 2007 Plan. In addition, the Company maintains an employee stock purchase plan (the “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 from 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 months ended March 31, 2024 and 2023, the Company recorded the following stock-based compensation expense in selling, general, administrative and development expense: Three Months Ended March 31, 2024 2023 Stock-based compensation expense $ 64.9 $ 65.5 Stock Options —As of March 31, 2024, there was no unrecognized compensation expense related to unvested stock options. The Company’s option activity for the three months ended March 31, 2024 was as follows (shares disclosed in full amounts): Number of Options Outstanding as of January 1, 2024 766,955 Exercised (166,886) Forfeited — Expired — Outstanding as of March 31, 2024 600,069 Restricted Stock Units— As of March 31, 2024, total unrecognized compensation expense related to unvested RSUs granted under the 2007 Plan was $258.1 million and is expected to be recognized over a weighted average period of approximately two years. Vesting of RSUs is subject generally to the employee’s continued employment or death, disability or qualified retirement (each as defined in the applicable RSU award agreement). Performance-Based Restricted Stock Units— During the three months ended March 31, 2024, the Company’s Compensation Committee (the “Compensation Committee”) granted an aggregate of 87,550 PSUs (the “2024 PSUs”) to its executive officers and established the performance and market metrics for these awards. During the years ended December 31, 2023 and 2022, the Compensation Committee granted an aggregate of 118,684 PSUs (the “2023 PSUs”) and 98,542 PSUs (the “2022 PSUs”), respectively, to its executive officers and established the performance metrics for these awards. Threshold, target and maximum parameters were established for the metrics for a three-year performance period with respect to each of the 2024 PSUs, the 2023 PSUs and the 2022 PSUs and will be used to calculate the number of shares that will be issuable when each award vests, which may range from zero to 200% of the target amounts. At the end of each three-year performance period, the number of shares that vest will depend on the degree of achievement against the pre-established goals. PSUs will be paid out in common stock at the end of each performance period, subject generally to the executive’s continued employment or death, disability or qualified retirement (each as defined in the applicable PSU award agreement). PSUs will accrue dividend equivalents prior to vesting, which will be paid out only in respect of shares that actually vest. The 2024 PSUs include a market condition component based on relative total shareholder return as measured against the REIT constituents included in the S&P 500 Index. For the component of the 2024 PSUs subject to a market condition, fair value is determined using a Monte Carlo simulation model, which uses multiple input variables to determine the probability of satisfying the market condition requirements. The grant date fair value of the market condition component of the 2024 PSUs is $216.11. Key assumptions used to apply this pricing model were as follows: Three Months Ended March 31, 2024 Expected term (years) 2.81 Risk-free interest rate 4.31 % Annualized volatility 26.75 % Restricted Stock Units and Performance-Based Restricted Stock Units —The Company’s RSU and PSU activity for the three months ended March 31, 2024 was as follows (shares disclosed in full amounts): RSUs PSUs Outstanding as of January 1, 2024 (1) 1,638,711 363,488 Granted (2) 688,313 87,550 Vested and Released (3) (639,358) (97,124) Forfeited (8,510) (1,337) Outstanding as of March 31, 2024 1,679,156 352,577 Vested and deferred as of March 31, 2024 (4) 8,502 21,961 _______________ (1) PSUs consist of the target number of shares issuable at the end of the three-year performance period for the outstanding 2023 PSUs and the outstanding 2022 PSUs, or 118,684 shares and 98,542 shares, respectively, the shares issuable at the end of the three-year performance period for the PSUs granted in 2021 (the “2021 PSUs”) based on achievement against the performance metrics for the three-year performance period, or 127,318 shares and the target remaining number of shares issuable at the end of the one-year performance period for PSUs granted to certain non-executive employees during the year ended December 31, 2023, net of forfeitures, or 18,944 shares. (2) PSUs consist of the target number of shares issuable at the end of the three-year performance period for the 2024 PSUs, or 87,550 shares. (3) PSUs consist of shares vested pursuant to the 2021 PSUs. There are no additional shares to be earned related to the 2021 PSUs. As of March 31, 2024, 8,233 earned shares remain outstanding and will vest in June 2024. (4) Vested and deferred RSUs and PSUs are related to deferred compensation for certain former employees. During the three months ended March 31, 2024, the Company recorded $9.1 million in stock-based compensation expense for equity awards in which the performance goals have been established and were probable of being achieved. The remaining unrecognized compensation expense related to these awards at March 31, 2024 was $22.7 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.

EQUITY

EQUITY	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
EQUITY	EQUITY Sales of Equity Securities —The Company receives proceeds from sales of its equity securities pursuant to the ESPP and upon exercise of stock options granted under the 2007 Plan. During the three months ended March 31, 2024, the Company received an aggregate of $13.9 million in proceeds upon exercises of stock options. Stock Repurchase Programs —In March 2011, the Company’s Board of Directors approved a stock repurchase program, pursuant to which the Company is authorized to repurchase up to $1.5 billion of its common stock (the “2011 Buyback”). In December 2017, the Board of Directors approved an additional stock repurchase program, pursuant to which the Company is authorized to repurchase up to $2.0 billion of its common stock (the “2017 Buyback,” and, together with the 2011 Buyback, the “Buyback Programs”). Under the Buyback Programs, the Company is authorized to purchase shares from time to time through open market purchases, in privately negotiated transactions not to exceed market prices, and (with respect to such open market purchases) pursuant to plans adopted in accordance with Rule 10b5-1 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), in accordance with securities laws and other legal requirements and subject to market conditions and other factors. During the three months ended March 31, 2024, there were no repurchases under either of the Buyback Programs. As of March 31, 2024, the Company has repurchased a total of 14,451,325 shares of its common stock under the 2011 Buyback for an aggregate of $1.5 billion, including commissions and fees. As of March 31, 2024, the Company has not made any repurchases under the 2017 Buyback. The Company expects to fund any further repurchases of its common stock through a combination of cash on hand, cash generated by operations and borrowings under its credit facilities. Repurchases under the Buyback Programs are subject to, among other things, the Company having available cash to fund the repurchases. Distributions —During the three months ended March 31, 2024, the Company declared or paid the following cash distributions (per share data reflects actual amounts): Declaration Date Payment Date Record Date Distribution per share Aggregate Payment Amount (1) Common Stock March 14, 2024 April 26, 2024 April 12, 2024 $ 1.62 $ 756.5 December 13, 2023 February 1, 2024 December 28, 2023 $ 1.70 $ 792.7 _______________ (1) Does not include amounts accrued for distributions payable related to unvested restricted stock units. During the three months ended March 31, 2023, the Company declared or paid the following cash distributions (per share data reflects actual amounts): Declaration Date Payment Date Record Date Distribution per share Aggregate Payment Amount (1) Common Stock March 8, 2023 April 28, 2023 April 14, 2023 $ 1.56 $ 727.0 December 7, 2022 February 2, 2023 December 28, 2022 $ 1.56 $ 726.3 _______________ (1) Does not include amounts accrued for distributions payable related to unvested restricted stock units. The Company accrues distributions on unvested restricted stock units, which are payable upon vesting. As of March 31, 2024, the amount accrued for distributions payable related to unvested restricted stock units was $15.4 million. During the three months ended March 31, 2024 and 2023, the Company paid $9.4 million and $6.6 million of distributions upon the vesting of restricted stock units, respectively. 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.

NONCONTROLLING INTERESTS

NONCONTROLLING INTERESTS	3 Months Ended
	Mar. 31, 2024
Noncontrolling Interest [Abstract]
NONCONTROLLING INTERESTS	NONCONTROLLING INTERESTS European Interests— As of March 31, 2024, ATC Europe consists of the Company’s operations in France, Germany and Spain. The Company currently holds a 52% controlling interest in ATC Europe, with Caisse de dépôt et placement du Québec (“CDPQ”) and Allianz insurance companies and funds managed by Allianz Capital Partners GmbH, including the Allianz European Infrastructure Fund (collectively, “Allianz”) holding 30% and 18% noncontrolling interests, respectively. ATC Europe holds a 100% interest in the subsidiaries that consist of the Company’s operations in France and an 87% and an 83% controlling interest in the subsidiaries that consist of the Company’s operations in Germany and Spain, respectively, with PGGM holding a 13% and a 17% noncontrolling interest in each respective subsidiary. Bangladesh Partnership —In 2021 , the Company acquired a 51% controlling interest in Kirtonkhola Tower Bangladesh Limited (“KTBL”) for 900 million Bangladeshi Taka (approximately $10.6 million at the date of closing). Confidence Group holds a 49% noncontrolling interest in KTBL. Stonepeak Transaction —In 2022, the Company entered into agreements pursuant to which certain investment vehicles affiliated with Stonepeak Partners LP (such investment vehicles, collectively, “Stonepeak”) acquired a noncontrolling ownership interest in the Company’s U.S. data center business for total aggregate consideration of $3.1 billion, through an investment in common equity and mandatorily convertible preferred equity (the “Stonepeak Transaction”). As of March 31, 2024, the Company holds a common equity interest of approximately 72% in its U.S. data center business, with Stonepeak holding approximately 28% of the outstanding common equity and 100% of the outstanding mandatorily convertible preferred equity. On a fully converted basis, which is expected to occur four years from August 2022, and on the basis of the currently outstanding equity, the Company will hold a controlling ownership interest of approximately 64%, with Stonepeak holding approximately 36%. The mandatorily convertible preferred equity, which accrues dividends at 5.0%, will convert into common equity on a one for one basis, subject to adjustment that will be measured on the conversion date. Dividends to noncontrolling interests— Certain of the Company’s subsidiaries may, from time to time, declare dividends. During the three months ended March 31, 2024, the Company’s U.S. data center business declared distributions of $11.5 million related to the outstanding Stonepeak mandatorily convertible preferred equity (the “Stonepeak Preferred Distributions”). As of March 31, 2024, the amount accrued for Stonepeak Preferred Distributions was $11.5 million. Beginning in January 2024, pursuant to the terms of the ownership agreement with Stonepeak, on a quarterly basis, the Company’s U.S. data center business will distribute common dividends to the Company and to Stonepeak in proportion to their respective equity interests in the Company’s U.S. data center business (the “Stonepeak Common Dividend”). During the three months ended March 31, 2024, the Company’s U.S. data center business made distributions of $91.7 million related to the Stonepeak Common Dividend for the period from the initial closing of the Stonepeak Transaction in August 2022 through December 31, 2023, which was accrued for as of December 31, 2023. The $91.7 million distribution during the three months ended March 31, 2024 included a noncash distribution of $37.5 million made in lieu of a common equity contribution from Stonepeak. During the three months ended March 31, 2024, pursuant to the terms of the ownership agreements, ATC Europe C.V., one of the Company’s subsidiaries in the Netherlands, declared and paid a dividend of 170.0 million EUR (approximately $183.2 million at the date of payment), pursuant to the terms of the ownership agreements, to the Company, CDPQ and Allianz in proportion to their respective equity interests in ATC Europe C.V. During the three months ended March 31, 2024, pursuant to the terms of the ownership agreements, AT Rhine C.V., one of the Company’s subsidiaries in Germany, declared and paid a dividend of 45.0 million EUR (approximately $48.6 million at the date of payment), pursuant to the terms of the ownership agreements, to ATC Europe and PGGM in proportion to their respective equity interests in AT Rhine C.V. The changes in noncontrolling interests were as follows: Three Months Ended March 31, 2024 2023 Balance as of January 1, $ 6,667.2 $ 6,836.1 Net income (loss) attributable to noncontrolling interests 4.3 (20.8) Foreign currency translation adjustment attributable to noncontrolling interests, net of tax (92.7) 39.9 Contributions from noncontrolling interest holders (1) 138.9 — Distributions to noncontrolling interest holders (103.8) (11.5) Balance as of March 31, $ 6,613.9 $ 6,843.7 _______________ (1) During the three months ended March 31, 2024, primarily includes contributions from Stonepeak of $137.3 million, including a noncash contribution of $37.5 million made in lieu of Stonepeak’s receipt of the Stonepeak Common Dividend.

EARNINGS PER COMMON SHARE

EARNINGS PER COMMON SHARE	3 Months Ended
	Mar. 31, 2024
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 (shares in thousands, except per share data): Three Months Ended March 31, 2024 2023 Net income attributable to American Tower Corporation common stockholders $ 917.4 $ 335.8 Basic weighted average common shares outstanding 466,519 465,741 Dilutive securities 1,141 1,069 Diluted weighted average common shares outstanding 467,660 466,810 Basic net income attributable to American Tower Corporation common stockholders per common share $ 1.97 $ 0.72 Diluted net income attributable to American Tower Corporation common stockholders per common share $ 1.96 $ 0.72 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 March 31, 2024 2023 Restricted stock units 126 5

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2024
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 currently provides for the lease, sublease or management of approximately 11,200 wireless communications sites, which commenced on March 27, 2015. The average term of the lease or sublease for all communications 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 1,800 towers, which commenced between December 2000 and August 2004. Substantially all of the towers are part of the Trust Securitizations. 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 March 31, 2024, the Company has purchased an aggregate of approximately 600 of the subleased towers which are subject to the applicable agreement. The aggregate purchase option price for the remaining towers leased and subleased is $1.1 billion and includes per annum accretion through the applicable expiration of the lease or sublease of a site. For all such sites, AT&T has the right to continue to lease the reserved space through June 30, 2025 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 five successive five-year terms. Other Contingencies

BUSINESS SEGMENTS

BUSINESS SEGMENTS	3 Months Ended
	Mar. 31, 2024
Segment Reporting [Abstract]
BUSINESS SEGMENTS	BUSINESS SEGMENTS Property Communications Sites and Related Communications Infrastructure —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. The Company has historically reported these operations on a geographic basis. Data Centers —The Company’s Data Centers segment relates to data center facilities and related assets that the Company owns and operates in the United States. The Data Centers segment offers different types of leased land and related services from, and requires different resources, skill sets and marketing strategies than the existing property operating segment in the U.S. & Canada. As of March 31, 2024, the Company’s property operations consisted of the following: • U.S. & Canada: property operations in Canada and the United States; • Asia-Pacific: property operations in Australia, Bangladesh, India, New Zealand and the Philippines; • Africa: property operations in Burkina Faso, Ghana, Kenya, Niger, Nigeria, South Africa and Uganda; • Europe: property operations in France, Germany and Spain; • Latin America: property operations in Argentina, Brazil, Chile, Colombia, Costa Rica, Mexico, Paraguay and Peru; and • Data Centers: data center property operations in the United States. Services The Company’s Services segment offers tower-related services in the United States, including AZP, structural and mount analyses, and construction management, which primarily support its site leasing business, including the addition of new tenants and equipment on its communications 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 2023 Form 10-K and as updated in note 1 above. 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 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. 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 months ended March 31, 2024 and 2023 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. Property Total Services Other Total Three Months Ended March 31, 2024 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Segment revenues $ 1,310.7 $ 326.6 $ 292.0 $ 204.5 $ 445.5 $ 224.6 $ 2,803.9 $ 30.2 $ 2,834.1 Segment operating expenses 204.3 170.7 92.7 73.5 140.3 92.9 774.4 13.9 788.3 Segment gross margin 1,106.4 155.9 199.3 131.0 305.2 131.7 2,029.5 16.3 2,045.8 Segment selling, general, administrative and development expense (1) 36.6 12.8 14.9 15.8 27.8 17.2 125.1 4.9 130.0 Segment operating profit $ 1,069.8 $ 143.1 $ 184.4 $ 115.2 $ 277.4 $ 114.5 $ 1,904.4 $ 11.4 $ 1,915.8 Stock-based compensation expense $ 64.9 64.9 Other selling, general, administrative and development expense 62.1 62.1 Depreciation, amortization and accretion 549.4 549.4 Other expense (2) 208.5 208.5 Income from continuing operations before income taxes $ 1,030.9 Total assets $ 26,879.0 $ 3,821.9 $ 3,972.3 $ 11,676.0 $ 9,097.7 $ 10,455.1 $ 65,902.0 $ 67.4 $ 709.6 $ 66,679.0 _______________ (1) Segment selling, general, administrative and development expenses exclude stock-based compensation expense of $64.9 million. (2) Primarily includes interest expense, partially offset by gains from foreign currency exchange rate fluctuations. Property Total Services Other Total Three Months Ended March 31, 2023 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Segment revenues $ 1,287.6 $ 251.1 $ 317.0 $ 191.7 $ 464.1 $ 203.0 $ 2,714.5 $ 52.7 $ 2,767.2 Segment operating expenses 205.3 168.4 118.5 73.1 137.9 83.8 787.0 19.1 806.1 Segment gross margin 1,082.3 82.7 198.5 118.6 326.2 119.2 1,927.5 33.6 1,961.1 Segment selling, general, administrative and development expense (1) 40.8 8.8 21.4 14.6 29.7 17.5 132.8 5.7 138.5 Segment operating profit $ 1,041.5 $ 73.9 $ 177.1 $ 104.0 $ 296.5 $ 101.7 $ 1,794.7 $ 27.9 $ 1,822.6 Stock-based compensation expense $ 65.5 65.5 Other selling, general, administrative and development expense 59.9 59.9 Depreciation, amortization and accretion 794.1 794.1 Other expense (2) 534.7 534.7 Income from continuing operations before income taxes $ 368.4 Total assets $ 26,657.4 $ 3,879.7 $ 4,632.4 $ 11,609.5 $ 8,741.0 $ 10,632.5 $ 66,152.5 $ 125.2 $ 540.0 $ 66,817.7 _______________ (1) Segment selling, general, administrative and development expenses exclude stock-based compensation expense of $65.5 million. (2) Primarily includes interest expense and losses from foreign currency exchange rate fluctuations. Three months ended March 31, 2023 also includes a loss on the sale of one of the Company’s subsidiaries in Mexico that held fiber assets of $80.0 million and $29.8 million in impairment charges.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2024
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS Sale of the VIL Shares—

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 31, 2024 shares
Trading Arrangements, by Individual
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Steven O Vondran [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Steven O. Vondran, our President and Chief Executive Officer, entered into a pre-arranged stock trading plan on March 6, 2024. Mr. Vondran’s plan provides for the potential exercise of vested stock options and the associated sale of up to 21,537 shares of our common stock between June 5, 2024 and March 10, 2025.
Name	Steven O. Vondran
Title	President and Chief Executive Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	March 6, 2024
Arrangement Duration	278 days
Aggregate Available	21,537

BASIS OF PRESENTATION AND SIG_2

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation and Basis of Presentation	Principles of Consolidation and Basis of Presentation
Reportable Segments	Reportable Segments —The Company reports its results in seven segments – U.S. & Canada property, Asia-Pacific property, Africa property, Europe property, Latin America property, Data Centers and Services, which are discussed further in note 14.
Property, Plant and Equipment, Policy	Property and Equipment —The Company finalized its review of the estimated useful lives of its tower assets during the three months ended March 31, 2024. The Company now has over 20 years of operating history, and determined that it should modify its current estimates for asset lives based on its historical operating experience. The Company retained an independent consultant to assist the Company in completing this review and analysis. The Company previously depreciated its towers on a straight-line basis over the shorter of the term of the underlying ground lease (including
Asset Retirement Obligations	Asset Retirement Obligations
Revenue	Revenue —The Company’s revenue is derived from leasing the right to use its communications sites, the land on which the sites are located, the land underlying its customers’ sites and the space in its data center facilities (the “lease component”) and from the reimbursement of costs incurred by the Company in operating the communications sites and data center facilities and supporting its customers’ equipment as well as other services and contractual rights (the “non-lease component”). Most of the Company’s revenue is derived from leasing arrangements and is accounted for as lease revenue unless the timing and pattern of revenue recognition of the non-lease component differs from the lease component. If the timing and pattern of the non-lease component revenue recognition differs from that of the lease component, the Company separately determines the stand-alone selling prices and pattern of revenue recognition for each performance obligation. Revenue related to distributed antenna system (“DAS”) networks and fiber and other related assets results from agreements with customers that are generally not accounted for as leases. Non-lease property revenue —Non-lease property revenue consists primarily of revenue generated from DAS networks, fiber and other property related revenue. DAS networks and fiber arrangements generally require that the Company provide the tenant the right to use available capacity on the applicable communications infrastructure. Performance obligations are satisfied over time for the duration of the arrangements. Non-lease property revenue also includes revenue generated from interconnection offerings in the Company’s data center facilities. Interconnection offerings are generally contracted on a month-to-month basis and are cancellable by the Company or the data center customer at any time. Performance obligations are satisfied over time for the duration of the arrangements. Other property related revenue streams, which include site inspections, are not material on either an individual or consolidated basis. There were no material changes in the receivables, contract assets and contract liabilities from contracts with customers for the three months ended March 31, 2024. Services revenue
Accounting Standards Updates	Accounting Standards Updates —In November 2023, the Financial Accounting Standards Board (“FASB”) issued guidance which is intended to improve reportable segment disclosure requirements, primarily through additional disclosures about significant segment expenses. The standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of this guidance on its consolidated financial statements and related disclosures. In December 2023, the FASB issued guidance which requires public entities to provide enhanced income tax disclosures on an annual basis. The new guidance requires an expanded rate reconciliation and the disaggregation of cash taxes paid by U.S. federal, U.S. state and foreign jurisdictions. The updated guidance is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the impact of this guidance on its consolidated financial statements and related disclosures. SEC Rule Changes — In March 2024, the SEC issued Final Rule No. 33-11275, “The Enhancement and Standardization of Climate-Related Disclosures for Investors.” If such rule remains in effect, the rule will require registrants to provide certain climate-related information in their registration statements and annual reports. The rule requires registrants to provide climate related disclosures, including, but not limited to, (i) material Scope 1 and Scope 2 greenhouse gas emissions, (ii) governance and oversight of material climate-related risks, (iii) the material impact of climate risks on the registrant’s strategy, business model and outlook, (iv) risk management processes for material climate-related risks and (v) material climate targets and goals. The rule also requires disclosure of (x) financial statement effects of severe weather events and other natural conditions, (y) carbon offset and renewable energy credit information and (z) the impact of severe weather events and other natural conditions on estimates and assumptions. Disclosure requirements will begin phasing in for fiscal years beginning on or after January 1, 2025. In April 2024, the SEC issued an order staying implementation of such rule pending the resolution of certain challenges. The outcome of ongoing litigation is currently unknown. The Company is currently evaluating the potential impact of such rule on its consolidated financial statements and disclosures.

BASIS OF PRESENTATION AND SIG_3

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Cash and Cash Equivalents	The reconciliation of cash and cash equivalents and restricted cash reported within the applicable balance sheet that sum to the total of the same such amounts shown in the statements of cash flows is as follows: Three Months Ended March 31, 2024 2023 Cash and cash equivalents $ 2,389.1 $ 1,803.0 Restricted cash 127.6 122.4 Total cash, cash equivalents and restricted cash $ 2,516.7 $ 1,925.4
Schedule of Restrictions on Cash and Cash Equivalents	The reconciliation of cash and cash equivalents and restricted cash reported within the applicable balance sheet that sum to the total of the same such amounts shown in the statements of cash flows is as follows: Three Months Ended March 31, 2024 2023 Cash and cash equivalents $ 2,389.1 $ 1,803.0 Restricted cash 127.6 122.4 Total cash, cash equivalents and restricted cash $ 2,516.7 $ 1,925.4
Schedule of Revenue Disaggregated by Source and Geography	A summary of revenue disaggregated by source and geography is as follows: Three Months Ended March 31, 2024 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Total Non-lease property revenue $ 72.9 $ 2.2 $ 6.1 $ 3.5 $ 28.7 $ 31.6 $ 145.0 Services revenue 30.2 — — — — — 30.2 Total non-lease revenue $ 103.1 $ 2.2 $ 6.1 $ 3.5 $ 28.7 $ 31.6 $ 175.2 Property lease revenue 1,237.8 324.4 285.9 201.0 416.8 193.0 2,658.9 Total revenue $ 1,340.9 $ 326.6 $ 292.0 $ 204.5 $ 445.5 $ 224.6 $ 2,834.1 Three Months Ended March 31, 2023 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Total Non-lease property revenue $ 71.0 $ 2.3 $ 6.7 $ 3.4 $ 41.3 $ 28.3 $ 153.0 Services revenue 52.7 — — — — — 52.7 Total non-lease revenue $ 123.7 $ 2.3 $ 6.7 $ 3.4 $ 41.3 $ 28.3 $ 205.7 Property lease revenue 1,216.6 248.8 310.3 188.3 422.8 174.7 2,561.5 Total revenue $ 1,340.3 $ 251.1 $ 317.0 $ 191.7 $ 464.1 $ 203.0 $ 2,767.2

PREPAID AND OTHER CURRENT ASS_2

PREPAID AND OTHER CURRENT ASSETS (Tables)	3 Months Ended
	Mar. 31, 2024
Prepaid Expense and Other Assets, Current [Abstract]
Schedule of Prepaid and Other Current Assets	Prepaid and other current assets consisted of the following: As of March 31, 2024 December 31, 2023 Prepaid assets $ 98.9 $ 93.4 Prepaid income tax 127.3 102.9 Unbilled receivables 383.9 323.2 Value added tax and other consumption tax receivables 57.9 79.8 Other miscellaneous current assets (1) 316.6 347.6 Prepaid and other current assets $ 984.6 $ 946.9 _______________ (1) Includes the VIL OCDs and the VIL Shares (each as defined and further discussed in note 7).

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2024
Leases [Abstract]
Schedule of Future Minimum Rental Receipts Expected Under Operating Leases	Future minimum rental receipts expected under non-cancellable operating lease agreements as of March 31, 2024 were as follows: Fiscal Year Amount (1) (2) Remainder of 2024 $ 6,292.1 2025 7,870.7 2026 7,385.8 2027 7,173.0 2028 5,857.2 Thereafter 25,221.6 Total $ 59,800.4 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods. (2) Balances represent contractual amounts owed with no adjustments made for expected collectibility.
Schedule of Information About Other Lease-Related Balances	Information about other lease-related balances is as follows: As of March 31, 2024 December 31, 2023 Operating leases: Right-of-use asset $ 9,199.8 $ 8,878.8 Current portion of lease liability $ 715.2 $ 794.6 Lease liability 7,866.3 7,438.7 Total operating lease liability $ 8,581.5 $ 8,233.3
Schedule of Components of Operating Lease Cost	The weighted-average remaining lease terms and incremental borrowing rates are as follows: As of March 31, 2024 December 31, 2023 Operating leases: Weighted-average remaining lease term (years) (1) 13.7 11.6 Weighted-average incremental borrowing rate 6.7 % 5.8 % ______________ (1) As of March 31, 2024, reflects the change in estimated useful lives as described in note 1. The following table sets forth the components of lease cost: Three Months Ended March 31, 2024 2023 Operating lease cost $ 326.4 $ 306.7 Variable lease costs not included in lease liability (1) 89.2 109.1 ______________ (1) Primarily includes property tax paid on behalf of the landlord. Supplemental cash flow information is as follows: Three Months Ended March 31, 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (365.9) $ (342.6) Non-cash items: New operating leases (1) $ 39.1 $ 56.5 Operating lease modifications and reassessments (2) $ 593.9 $ 102.9 ______________ (1) Amount includes new operating leases and leases acquired in connection with acquisitions. (2)
Schedule of Maturity of Operating Lease Liabilities	Maturities of operating lease liabilities as of March 31, 2024 were as follows: Fiscal Year Operating Lease (1) Remainder of 2024 $ 880.2 2025 1,116.3 2026 1,062.8 2027 1,003.8 2028 943.0 Thereafter 8,346.5 Total lease payments 13,352.6 Less amounts representing interest (4,771.1) Total lease liability 8,581.5 Less current portion of lease liability 715.2 Non-current lease liability $ 7,866.3 _______________ (1) Balances are translated at the applicable period-end exchange rate, which may impact comparability between periods.

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Changes in the Carrying Value of Goodwill	The changes in the carrying value of goodwill for each of the Company’s business segments were as follows: Property Services Total U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Balance as of January 1, 2024 $ 4,638.6 $ 562.7 $ 497.7 $ 3,051.9 $ 966.1 $ 2,920.0 $ 2.0 $ 12,639.0 Effect of foreign currency translation (1.1) (1.3) 1.6 (68.8) (12.6) — — (82.2) Balance as of March 31, 2024 $ 4,637.5 $ 561.4 $ 499.3 $ 2,983.1 $ 953.5 $ 2,920.0 $ 2.0 $ 12,556.8
Schedule of Other Intangible Assets Subject to Amortization	The Company’s other intangible assets subject to amortization consisted of the following: As of March 31, 2024 As of December 31, 2023 Estimated Useful Gross Accumulated Net Book Gross Accumulated Net Book Acquired network location intangibles (2) Up to 30 $ 5,930.6 $ (2,795.5) $ 3,135.1 $ 5,981.5 $ (2,775.8) $ 3,205.7 Acquired tenant-related intangibles Up to 30 18,728.8 (6,815.0) 11,913.8 18,894.5 (6,698.6) 12,195.9 Acquired licenses and other intangibles 2-30 1,535.5 (465.1) 1,070.4 1,561.1 (442.0) 1,119.1 Total other intangible assets $ 26,194.9 $ (10,075.6) $ 16,119.3 $ 26,437.1 $ (9,916.4) $ 16,520.7 _______________ (1) As of March 31, 2024, reflects the change in estimated useful lives as described in note 1. (2) Beginning January 1, 2024, acquired network location intangibles are amortized over the remaining estimated useful life of the tower, taking into account residual value, generally up to 30 years, as the Company considers these intangibles to be directly related to the tower assets. Prior to January 1, 2024, acquired network location intangibles were amortized over the shorter of the term of the corresponding ground lease, taking into consideration lease renewal options and residual value, or the estimated useful life of the tower, generally up to 20 years.
Schedule of 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: Fiscal Year Amount (1) Remainder of 2024 $ 707.8 2025 921.9 2026 881.5 2027 869.5 2028 858.0 2029 839.0 ______________ (1)

ACCRUED EXPENSES (Tables)

ACCRUED EXPENSES (Tables)	3 Months Ended
	Mar. 31, 2024
Accrued Liabilities, Current [Abstract]
Schedule of Accrued Expenses	Accrued expenses consisted of the following: As of March 31, 2024 December 31, 2023 Accrued construction costs $ 131.9 $ 183.8 Accrued income tax payable 26.9 21.0 Accrued pass-through costs 97.0 77.4 Amounts payable for acquisitions 1.9 27.7 Amounts payable to tenants 99.5 103.3 Accrued property and real estate taxes 294.5 295.5 Accrued rent 75.6 75.1 Payroll and related withholdings 98.2 147.4 Other accrued expenses 308.6 349.4 Total accrued expenses $ 1,134.1 $ 1,280.6

LONG-TERM OBLIGATIONS (Tables)

LONG-TERM OBLIGATIONS (Tables)	3 Months Ended
	Mar. 31, 2024
Debt Disclosure [Abstract]
Schedule of Long-Term Debt Instruments	Outstanding amounts under the Company’s long-term obligations, reflecting discounts, premiums and debt issuance costs, consisted of the following: As of March 31, 2024 December 31, 2023 Maturity Date 2021 Multicurrency Credit Facility (1) (2) $ 1,011.6 $ 723.4 July 1, 2026 2021 Term Loan (1) 997.2 997.0 January 31, 2027 2021 Credit Facility (1) 2,038.4 1,603.4 July 1, 2028 2021 EUR Three Year Delayed Draw Term Loan (1) (2) 890.1 910.7 May 28, 2024 0.600% senior notes (3) — 500.0 N/A 5.00% senior notes (4) — 1,000.1 N/A 3.375% senior notes 650.0 649.7 May 15, 2024 2.950% senior notes 648.6 648.2 January 15, 2025 2.400% senior notes 748.8 748.5 March 15, 2025 1.375% senior notes (5) 538.0 550.0 April 4, 2025 4.000% senior notes 748.4 748.1 June 1, 2025 1.300% senior notes 498.5 498.3 September 15, 2025 4.400% senior notes 498.9 498.7 February 15, 2026 1.600% senior notes 697.7 697.4 April 15, 2026 1.950% senior notes (5) 537.4 549.6 May 22, 2026 1.450% senior notes 596.3 595.9 September 15, 2026 3.375% senior notes 995.1 994.7 October 15, 2026 3.125% senior notes 399.0 398.9 January 15, 2027 2.750% senior notes 747.3 747.0 January 15, 2027 0.450% senior notes (5) 805.9 824.3 January 15, 2027 0.400% senior notes (5) 536.1 548.2 February 15, 2027 3.650% senior notes 645.2 644.8 March 15, 2027 4.125% senior notes (5) 643.9 658.6 May 16, 2027 3.55% senior notes 747.3 747.1 July 15, 2027 3.600% senior notes 696.3 696.0 January 15, 2028 0.500% senior notes (5) 804.4 822.8 January 15, 2028 1.500% senior notes 647.3 647.1 January 31, 2028 5.500% senior notes 694.0 693.6 March 15, 2028 5.250% senior notes 644.2 643.9 July 15, 2028 5.800% senior notes 743.7 743.4 November 15, 2028 5.200% senior notes 642.7 — February 15, 2029 3.950% senior notes 594.0 593.7 March 15, 2029 0.875% senior notes (5) 805.1 823.7 May 21, 2029 3.800% senior notes 1,639.1 1,638.6 August 15, 2029 2.900% senior notes 744.5 744.2 January 15, 2030 2.100% senior notes 743.4 743.1 June 15, 2030 0.950% senior notes (5) 533.8 546.0 October 5, 2030 1.875% senior notes 793.6 793.3 October 15, 2030 2.700% senior notes 695.2 695.0 April 15, 2031 4.625% senior notes (5) 533.0 545.2 May 16, 2031 2.300% senior notes 692.9 692.7 September 15, 2031 1.000% senior notes (5) 695.4 711.5 January 15, 2032 4.050% senior notes 643.1 642.9 March 15, 2032 5.650% senior notes 790.8 790.6 March 15, 2033 1.250% senior notes (5) 533.4 545.8 May 21, 2033 5.550% senior notes 840.8 840.6 July 15, 2033 5.900% senior notes 741.7 741.5 November 15, 2033 5.450% senior notes 640.0 — February 15, 2034 3.700% senior notes 592.5 592.4 October 15, 2049 3.100% senior notes 1,038.6 1,038.6 June 15, 2050 2.950% senior notes 1,023.3 1,023.2 January 15, 2051 Total American Tower Corporation debt 36,806.5 36,472.0 Series 2015-2 notes (6) 524.2 524.1 June 16, 2025 Series 2018-1A securities (7) 497.0 496.8 March 15, 2028 Series 2023-1A securities (8) 1,285.3 1,284.4 March 15, 2028 Other subsidiary debt (9) 126.7 123.6 Various Total American Tower subsidiary debt 2,433.2 2,428.9 Finance lease obligations 19.8 20.6 Total 39,259.5 38,921.5 Less current portion of long-term obligations (3,067.6) (3,187.5) Long-term obligations $ 36,191.9 $ 35,734.0 _______________ (1) Accrues interest at a variable rate. (2) Reflects borrowings denominated in Euro (“EUR”) and, for the 2021 Multicurrency Credit Facility (as defined below), reflects borrowings denominated in both EUR and U.S. Dollars (“USD”). (3) Repaid in full on January 12, 2024 using borrowings under the 2021 Multicurrency Credit Facility. (4) Repaid in full on February 14, 2024 using borrowings under the 2021 Multicurrency Credit Facility. (5) Notes are denominated in EUR. (6) Maturity date reflects the anticipated repayment date; final legal maturity is June 15, 2050. (7) Maturity date reflects the anticipated repayment date; final legal maturity is March 15, 2048. (8) Maturity date reflects the anticipated repayment date; final legal maturity is March 15, 2053. (9) Includes amounts drawn under letters of credit in Nigeria, which are denominated in USD, and borrowings under an unsecured term loan in India (the “India Term Loan”), which is denominated in INR. In January 2024, the Company amended the India Term Loan to extend the maturity date to December 31, 2024. The key terms of the Notes are as follows: Senior Notes Aggregate Principal Amount (in millions) Issue Date and Interest Accrual Date Maturity Date Contractual Interest Rate First Interest Payment Interest Payments Due (1) Par Call Date (2) 5.200% Notes $ 650.0 March 7, 2024 February 15, 2029 5.200% August 15, 2024 February 15 and August 15 January 15, 2029 5.450% Notes $ 650.0 March 7, 2024 February 15, 2034 5.450% August 15, 2024 February 15 and August 15 November 15, 2033 ___________ (1) Accrued and unpaid interest on USD denominated notes is payable in USD semi-annually in arrears and will be computed from the issue date on the basis of a 360-day year comprised of twelve 30-day months. (2) The Company may redeem the 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 Notes on or after the par call date, the Company will not be required to pay a make-whole premium.
Schedule of Maturities of Long-Term Debt	As of March 31, 2024, the key terms under the 2021 Multicurrency Credit Facility, the 2021 Credit Facility, the Company’s $1.0 billion unsecured term loan, as amended and restated in December 2021, as further amended (the “2021 Term Loan”) and the Company’s 825.0 million EUR unsecured term loan, as amended in December 2021 (the “2021 EUR Three Year Delayed Draw Term Loan”) were as follows: Outstanding Principal Balance Undrawn letters of credit Maturity Date Current margin over SOFR or EURIBOR (1) Current commitment fee (2) 2021 Multicurrency Credit Facility $ 1,011.6 $ 3.5 July 1, 2026 (3) 1.125 % 0.110 % 2021 Credit Facility 2,038.4 30.4 July 1, 2028 (3) 1.125 % 0.110 % 2021 Term Loan 1,000.0 N/A January 31, 2027 1.125 % N/A 2021 EUR Three Year Delayed Draw Term Loan 890.2 N/A May 28, 2024 1.125 % N/A _______________ (1) SOFR applies to the USD denominated borrowings under the 2021 Multicurrency Credit Facility, the 2021 Credit Facility and the 2021 Term Loan. Euro Interbank Offer Rate (“EURIBOR”) applies to the EUR denominated borrowings under the 2021 Multicurrency Credit Facility and all of the borrowings under the 2021 EUR Three Year Delayed Draw Term Loan. (2) Fee on undrawn portion of each credit facility. (3)

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets and Liabilities Measured 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: March 31, 2024 December 31, 2023 Fair Value Measurements Using Fair Value Measurements Using Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets: Investments in equity securities (1) $ 13.5 $ 5.3 — $ 28.2 $ 5.3 — VIL Shares — $ 172.7 — — — — VIL OCDs — $ 19.2 — — $ 192.3 — _______________ (1) Investments in equity securities are recorded in Notes receivable and other non-current assets in the consolidated balance sheet at fair value. Unrealized holding gains and losses for equity securities are recorded in Other income (expense) in the consolidated statements of operations in the current period. During the three months ended March 31, 2024 and 2023, the Company recognized unrealized (losses) gains of $(14.7) million and $1.2 million, respectively, for equity securities held as of March 31, 2024.

INCOME TAXES (Tables)

INCOME TAXES (Tables)	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Schedule of Penalties and Income Tax-Related Interest Expense	The Company recorded the following penalties and income tax-related interest expense during the three months ended March 31, 2024 and 2023: Three Months Ended March 31, 2024 2023 Penalties and income tax-related interest expense $ 5.5 $ 2.8

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Schedule of Stock-Based Compensation Expenses	During the three months ended March 31, 2024 and 2023, the Company recorded the following stock-based compensation expense in selling, general, administrative and development expense: Three Months Ended March 31, 2024 2023 Stock-based compensation expense $ 64.9 $ 65.5
Schedule of Option Activity	The Company’s option activity for the three months ended March 31, 2024 was as follows (shares disclosed in full amounts): Number of Options Outstanding as of January 1, 2024 766,955 Exercised (166,886) Forfeited — Expired — Outstanding as of March 31, 2024 600,069
Schedule of Key Assumptions	Key assumptions used to apply this pricing model were as follows: Three Months Ended March 31, 2024 Expected term (years) 2.81 Risk-free interest rate 4.31 % Annualized volatility 26.75 %
Schedule of RSU Activity	The Company’s RSU and PSU activity for the three months ended March 31, 2024 was as follows (shares disclosed in full amounts): RSUs PSUs Outstanding as of January 1, 2024 (1) 1,638,711 363,488 Granted (2) 688,313 87,550 Vested and Released (3) (639,358) (97,124) Forfeited (8,510) (1,337) Outstanding as of March 31, 2024 1,679,156 352,577 Vested and deferred as of March 31, 2024 (4) 8,502 21,961 _______________ (1) PSUs consist of the target number of shares issuable at the end of the three-year performance period for the outstanding 2023 PSUs and the outstanding 2022 PSUs, or 118,684 shares and 98,542 shares, respectively, the shares issuable at the end of the three-year performance period for the PSUs granted in 2021 (the “2021 PSUs”) based on achievement against the performance metrics for the three-year performance period, or 127,318 shares and the target remaining number of shares issuable at the end of the one-year performance period for PSUs granted to certain non-executive employees during the year ended December 31, 2023, net of forfeitures, or 18,944 shares. (2) PSUs consist of the target number of shares issuable at the end of the three-year performance period for the 2024 PSUs, or 87,550 shares. (3) PSUs consist of shares vested pursuant to the 2021 PSUs. There are no additional shares to be earned related to the 2021 PSUs. As of March 31, 2024, 8,233 earned shares remain outstanding and will vest in June 2024. (4) Vested and deferred RSUs and PSUs are related to deferred compensation for certain former employees.
Schedule of PSU Activity	The Company’s RSU and PSU activity for the three months ended March 31, 2024 was as follows (shares disclosed in full amounts): RSUs PSUs Outstanding as of January 1, 2024 (1) 1,638,711 363,488 Granted (2) 688,313 87,550 Vested and Released (3) (639,358) (97,124) Forfeited (8,510) (1,337) Outstanding as of March 31, 2024 1,679,156 352,577 Vested and deferred as of March 31, 2024 (4) 8,502 21,961 _______________ (1) PSUs consist of the target number of shares issuable at the end of the three-year performance period for the outstanding 2023 PSUs and the outstanding 2022 PSUs, or 118,684 shares and 98,542 shares, respectively, the shares issuable at the end of the three-year performance period for the PSUs granted in 2021 (the “2021 PSUs”) based on achievement against the performance metrics for the three-year performance period, or 127,318 shares and the target remaining number of shares issuable at the end of the one-year performance period for PSUs granted to certain non-executive employees during the year ended December 31, 2023, net of forfeitures, or 18,944 shares. (2) PSUs consist of the target number of shares issuable at the end of the three-year performance period for the 2024 PSUs, or 87,550 shares. (3) PSUs consist of shares vested pursuant to the 2021 PSUs. There are no additional shares to be earned related to the 2021 PSUs. As of March 31, 2024, 8,233 earned shares remain outstanding and will vest in June 2024. (4) Vested and deferred RSUs and PSUs are related to deferred compensation for certain former employees.

EQUITY (Tables)

EQUITY (Tables)	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Schedule of Cash Distributions	During the three months ended March 31, 2024, the Company declared or paid the following cash distributions (per share data reflects actual amounts): Declaration Date Payment Date Record Date Distribution per share Aggregate Payment Amount (1) Common Stock March 14, 2024 April 26, 2024 April 12, 2024 $ 1.62 $ 756.5 December 13, 2023 February 1, 2024 December 28, 2023 $ 1.70 $ 792.7 _______________ (1) Does not include amounts accrued for distributions payable related to unvested restricted stock units. During the three months ended March 31, 2023, the Company declared or paid the following cash distributions (per share data reflects actual amounts): Declaration Date Payment Date Record Date Distribution per share Aggregate Payment Amount (1) Common Stock March 8, 2023 April 28, 2023 April 14, 2023 $ 1.56 $ 727.0 December 7, 2022 February 2, 2023 December 28, 2022 $ 1.56 $ 726.3 _______________ (1)

NONCONTROLLING INTERESTS (Table

NONCONTROLLING INTERESTS (Tables)	3 Months Ended
	Mar. 31, 2024
Noncontrolling Interest [Abstract]
Schedule of Changes in Noncontrolling Interests	The changes in noncontrolling interests were as follows: Three Months Ended March 31, 2024 2023 Balance as of January 1, $ 6,667.2 $ 6,836.1 Net income (loss) attributable to noncontrolling interests 4.3 (20.8) Foreign currency translation adjustment attributable to noncontrolling interests, net of tax (92.7) 39.9 Contributions from noncontrolling interest holders (1) 138.9 — Distributions to noncontrolling interest holders (103.8) (11.5) Balance as of March 31, $ 6,613.9 $ 6,843.7 _______________ (1) During the three months ended March 31, 2024, primarily includes contributions from Stonepeak of $137.3 million, including a noncash contribution of $37.5 million made in lieu of Stonepeak’s receipt of the Stonepeak Common Dividend.

EARNINGS PER COMMON SHARE (Tabl

EARNINGS PER COMMON SHARE (Tables)	3 Months Ended
	Mar. 31, 2024
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 (shares in thousands, except per share data): Three Months Ended March 31, 2024 2023 Net income attributable to American Tower Corporation common stockholders $ 917.4 $ 335.8 Basic weighted average common shares outstanding 466,519 465,741 Dilutive securities 1,141 1,069 Diluted weighted average common shares outstanding 467,660 466,810 Basic net income attributable to American Tower Corporation common stockholders per common share $ 1.97 $ 0.72 Diluted net income attributable to American Tower Corporation common stockholders per common share $ 1.96 $ 0.72
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 March 31, 2024 2023 Restricted stock units 126 5

BUSINESS SEGMENTS (Tables)

BUSINESS SEGMENTS (Tables)	3 Months Ended
	Mar. 31, 2024
Segment Reporting [Abstract]
Schedule of Summarized Financial Information Concerning the Company's Reportable Segments	Summarized financial information concerning the Company’s reportable segments for the three months ended March 31, 2024 and 2023 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. Property Total Services Other Total Three Months Ended March 31, 2024 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Segment revenues $ 1,310.7 $ 326.6 $ 292.0 $ 204.5 $ 445.5 $ 224.6 $ 2,803.9 $ 30.2 $ 2,834.1 Segment operating expenses 204.3 170.7 92.7 73.5 140.3 92.9 774.4 13.9 788.3 Segment gross margin 1,106.4 155.9 199.3 131.0 305.2 131.7 2,029.5 16.3 2,045.8 Segment selling, general, administrative and development expense (1) 36.6 12.8 14.9 15.8 27.8 17.2 125.1 4.9 130.0 Segment operating profit $ 1,069.8 $ 143.1 $ 184.4 $ 115.2 $ 277.4 $ 114.5 $ 1,904.4 $ 11.4 $ 1,915.8 Stock-based compensation expense $ 64.9 64.9 Other selling, general, administrative and development expense 62.1 62.1 Depreciation, amortization and accretion 549.4 549.4 Other expense (2) 208.5 208.5 Income from continuing operations before income taxes $ 1,030.9 Total assets $ 26,879.0 $ 3,821.9 $ 3,972.3 $ 11,676.0 $ 9,097.7 $ 10,455.1 $ 65,902.0 $ 67.4 $ 709.6 $ 66,679.0 _______________ (1) Segment selling, general, administrative and development expenses exclude stock-based compensation expense of $64.9 million. (2) Primarily includes interest expense, partially offset by gains from foreign currency exchange rate fluctuations. Property Total Services Other Total Three Months Ended March 31, 2023 U.S. & Canada Asia-Pacific Africa Europe Latin America Data Centers Segment revenues $ 1,287.6 $ 251.1 $ 317.0 $ 191.7 $ 464.1 $ 203.0 $ 2,714.5 $ 52.7 $ 2,767.2 Segment operating expenses 205.3 168.4 118.5 73.1 137.9 83.8 787.0 19.1 806.1 Segment gross margin 1,082.3 82.7 198.5 118.6 326.2 119.2 1,927.5 33.6 1,961.1 Segment selling, general, administrative and development expense (1) 40.8 8.8 21.4 14.6 29.7 17.5 132.8 5.7 138.5 Segment operating profit $ 1,041.5 $ 73.9 $ 177.1 $ 104.0 $ 296.5 $ 101.7 $ 1,794.7 $ 27.9 $ 1,822.6 Stock-based compensation expense $ 65.5 65.5 Other selling, general, administrative and development expense 59.9 59.9 Depreciation, amortization and accretion 794.1 794.1 Other expense (2) 534.7 534.7 Income from continuing operations before income taxes $ 368.4 Total assets $ 26,657.4 $ 3,879.7 $ 4,632.4 $ 11,609.5 $ 8,741.0 $ 10,632.5 $ 66,152.5 $ 125.2 $ 540.0 $ 66,817.7 _______________ (1) Segment selling, general, administrative and development expenses exclude stock-based compensation expense of $65.5 million. (2) Primarily includes interest expense and losses from foreign currency exchange rate fluctuations. Three months ended March 31, 2023 also includes a loss on the sale of one of the Company’s subsidiaries in Mexico that held fiber assets of $80.0 million and $29.8 million in impairment charges.

BASIS OF PRESENTATION AND SIG_4

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) ₨ in Millions, $ in Millions			3 Months Ended			12 Months Ended	48 Months Ended
	Jan. 04, 2024 USD ($)	Jan. 04, 2024 INR (₨)	Mar. 31, 2024 USD ($) reportableSegment	Mar. 31, 2024 INR (₨) reportableSegment	Mar. 31, 2023 USD ($)	Dec. 31, 2024 USD ($)	Aug. 31, 2026	Dec. 31, 2023 USD ($)
Concentration Risk [Line Items]
Number of reportable segments | reportableSegment			7	7
Right-of-use asset			$ 9,199.8					$ 8,878.8
Depreciation and amortization			(549.4)		$ (794.1)
Foreign currency exchange rate, remeasurement								11.95
Property straight-line revenue			79		112
Indian Customer
Concentration Risk [Line Items]
Deferred recognition of revenue					$ 33
Revenue recognized			29
Service Life
Concentration Risk [Line Items]
Right-of-use asset			515
Service Life | Forecast
Concentration Risk [Line Items]
Depreciation and amortization						$ 730
Change In Settlement Dates
Concentration Risk [Line Items]
Change in asset retirement obligations			470
Future cash outlay			$ 875
Change In Settlement Dates | Forecast
Concentration Risk [Line Items]
Accretion expense						$ 75
Tower
Concentration Risk [Line Items]
Estimated useful life of the tower (in years)			30 years					20 years
Minimum
Concentration Risk [Line Items]
Operating history, period			20 years	20 years
ATC TIPL
Concentration Risk [Line Items]
Dividends received			$ 115.1	₨ 9,603
Data Infrastructure Trust (DIT) | ATC TIPL
Concentration Risk [Line Items]
Consideration on sale of stocks	$ 2,500	₨ 210,000
Data Infrastructure Trust (DIT) | ATC TIPL | ATC TIPL
Concentration Risk [Line Items]
Equity method investment, ownership interest percentage	100%	100%
U.S. | Data Centers | Common Stock
Concentration Risk [Line Items]
Percentage of ownership after transaction (as a percent)			72%	72%
U.S. | Data Centers | Common Stock | Forecast
Concentration Risk [Line Items]
Percentage of ownership after transaction (as a percent)							64%
Ghana | Asset Benchmark | Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage			1%	1%
Ghana | Revenue Benchmark | Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage			1%	1%
ATC Europe
Concentration Risk [Line Items]
Noncontrolling ownership interest percentage (as a percent)			52%
Joint Venture - Bangladesh Operations
Concentration Risk [Line Items]
Ownership percentage (as a percent)			51%
Stonepeak | U.S. | Data Centers | Common Stock
Concentration Risk [Line Items]
Ownership percentage by noncontrolling owners (as a percent)			28%
Stonepeak | U.S. | Data Centers | Common Stock | Forecast
Concentration Risk [Line Items]
Ownership percentage by noncontrolling owners (as a percent)							36%
Stonepeak | U.S. | Data Centers | Preferred stock
Concentration Risk [Line Items]
Ownership percentage by noncontrolling owners (as a percent)			100%
Germany
Concentration Risk [Line Items]
Ownership percentage by noncontrolling owners (as a percent)			13%
Germany | ATC Europe
Concentration Risk [Line Items]
Noncontrolling ownership interest percentage (as a percent)			87%
Ownership percentage by noncontrolling owners (as a percent)			87%
Spain
Concentration Risk [Line Items]
Ownership percentage by noncontrolling owners (as a percent)			17%
Spain | ATC Europe
Concentration Risk [Line Items]
Noncontrolling ownership interest percentage (as a percent)			83%

BASIS OF PRESENTATION AND SIG_5

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 2,389.1	$ 1,973.3	$ 1,803
Restricted cash	127.6	120.1	122.4
Total cash, cash equivalents and restricted cash	$ 2,516.7	$ 2,093.4	$ 1,925.4	$ 2,140.7

BASIS OF PRESENTATION AND SIG_6

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Total non-lease revenue	$ 175.2	$ 205.7
Property lease revenue	2,658.9	2,561.5
Total revenue	2,834.1	2,767.2
U.S. & Canada
Disaggregation of Revenue [Line Items]
Total non-lease revenue	103.1	123.7
Property lease revenue	1,237.8	1,216.6
Total revenue	1,340.9	1,340.3
Asia-Pacific
Disaggregation of Revenue [Line Items]
Total non-lease revenue	2.2	2.3
Property lease revenue	324.4	248.8
Total revenue	326.6	251.1
Africa
Disaggregation of Revenue [Line Items]
Total non-lease revenue	6.1	6.7
Property lease revenue	285.9	310.3
Total revenue	292	317
Europe
Disaggregation of Revenue [Line Items]
Total non-lease revenue	3.5	3.4
Property lease revenue	201	188.3
Total revenue	204.5	191.7
Latin America
Disaggregation of Revenue [Line Items]
Total non-lease revenue	28.7	41.3
Property lease revenue	416.8	422.8
Total revenue	445.5	464.1
Data Centers
Disaggregation of Revenue [Line Items]
Total non-lease revenue	31.6	28.3
Property lease revenue	193	174.7
Total revenue	224.6	203
Non-lease property revenue
Disaggregation of Revenue [Line Items]
Total non-lease revenue	145	153
Non-lease property revenue | U.S. & Canada
Disaggregation of Revenue [Line Items]
Total non-lease revenue	72.9	71
Non-lease property revenue | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total non-lease revenue	2.2	2.3
Non-lease property revenue | Africa
Disaggregation of Revenue [Line Items]
Total non-lease revenue	6.1	6.7
Non-lease property revenue | Europe
Disaggregation of Revenue [Line Items]
Total non-lease revenue	3.5	3.4
Non-lease property revenue | Latin America
Disaggregation of Revenue [Line Items]
Total non-lease revenue	28.7	41.3
Non-lease property revenue | Data Centers
Disaggregation of Revenue [Line Items]
Total non-lease revenue	31.6	28.3
Services revenue
Disaggregation of Revenue [Line Items]
Total non-lease revenue	30.2	52.7
Services revenue | U.S. & Canada
Disaggregation of Revenue [Line Items]
Total non-lease revenue	30.2	52.7
Services revenue | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total non-lease revenue	0	0
Services revenue | Africa
Disaggregation of Revenue [Line Items]
Total non-lease revenue	0	0
Services revenue | Europe
Disaggregation of Revenue [Line Items]
Total non-lease revenue	0	0
Services revenue | Latin America
Disaggregation of Revenue [Line Items]
Total non-lease revenue	0	0
Services revenue | Data Centers
Disaggregation of Revenue [Line Items]
Total non-lease revenue	$ 0	$ 0

PREPAID AND OTHER CURRENT ASS_3

PREPAID AND OTHER CURRENT ASSETS (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid assets	$ 98.9	$ 93.4
Prepaid income tax	127.3	102.9
Unbilled receivables	383.9	323.2
Value added tax and other consumption tax receivables	57.9	79.8
Other miscellaneous current assets	316.6	347.6
Prepaid and other current assets	$ 984.6	$ 946.9

LEASES - Narrative (Details)

LEASES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Lessor, Lease, Description [Line Items]
Amortization of lease incentive, period	10 years
Right-of-use asset	$ 9,199.8		$ 8,878.8
Service Life
Lessor, Lease, Description [Line Items]
Right-of-use asset	515
Lease Agreements
Lessor, Lease, Description [Line Items]
Asset impairment charges	0	$ 0
Other Current Assets
Lessor, Lease, Description [Line Items]
Lease incentives	35.5
Other Noncurrent Assets
Lessor, Lease, Description [Line Items]
Lease incentives	$ 339.4

LEASES - Future Minimum Rental

LEASES - Future Minimum Rental Receipts Expected Under Operating Leases (Details) $ in Millions	Mar. 31, 2024 USD ($)
Leases [Abstract]
Remainder of 2024	$ 6,292.1
2025	7,870.7
2026	7,385.8
2027	7,173
2028	5,857.2
Thereafter	25,221.6
Total	$ 59,800.4

LEASES - Information About Othe

LEASES - Information About Other Lease-related Balances (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Operating leases:
Right-of-use asset	$ 9,199.8	$ 8,878.8
Current portion of lease liability	715.2	794.6
Lease liability	7,866.3	7,438.7
Total lease liability	$ 8,581.5	$ 8,233.3

LEASES - Weighted Average Lease

LEASES - Weighted Average Lease Terms and Discount Rates (Details)	Mar. 31, 2024	Dec. 31, 2023
Operating leases:
Weighted-average remaining lease term (years)	13 years 8 months 12 days	11 years 7 months 6 days
Weighted-average incremental borrowing rate	6.70%	5.80%

LEASES - Lease Costs (Details)

LEASES - Lease Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Leases [Abstract]
Operating lease cost	$ 326.4	$ 306.7
Variable lease costs not included in lease liability	$ 89.2	$ 109.1

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ (365.9)	$ (342.6)
Non-cash items:
New operating leases	39.1	56.5
Operating lease modifications and reassessments	$ 593.9	$ 102.9

LEASES - Maturities of Operatin

LEASES - Maturities of Operating Leases (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Remainder of 2024	$ 880.2
2025	1,116.3
2026	1,062.8
2027	1,003.8
2028	943
Thereafter	8,346.5
Total lease payments	13,352.6
Less amounts representing interest	(4,771.1)
Total lease liability	8,581.5	$ 8,233.3
Less current portion of lease liability	715.2	794.6
Non-current lease liability	$ 7,866.3	$ 7,438.7

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLE ASSETS - Changes in the Carrying Value of Goodwill (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 12,639
Effect of foreign currency translation	(82.2)
Goodwill, ending balance	12,556.8
U.S. & Canada
Goodwill [Roll Forward]
Goodwill, beginning balance	4,638.6
Effect of foreign currency translation	(1.1)
Goodwill, ending balance	4,637.5
Asia-Pacific
Goodwill [Roll Forward]
Goodwill, beginning balance	562.7
Effect of foreign currency translation	(1.3)
Goodwill, ending balance	561.4
Africa
Goodwill [Roll Forward]
Goodwill, beginning balance	497.7
Effect of foreign currency translation	1.6
Goodwill, ending balance	499.3
Europe
Goodwill [Roll Forward]
Goodwill, beginning balance	3,051.9
Effect of foreign currency translation	(68.8)
Goodwill, ending balance	2,983.1
Latin America
Goodwill [Roll Forward]
Goodwill, beginning balance	966.1
Effect of foreign currency translation	(12.6)
Goodwill, ending balance	953.5
Data Centers
Goodwill [Roll Forward]
Goodwill, beginning balance	2,920
Effect of foreign currency translation	0
Goodwill, ending balance	2,920
Services
Goodwill [Roll Forward]
Goodwill, beginning balance	2
Effect of foreign currency translation	0
Goodwill, ending balance	$ 2

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLE ASSETS - Other Intangible Assets Subject to Amortization (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 26,194.9	$ 26,437.1
Accumulated Amortization	(10,075.6)	(9,916.4)
Net Book Value	16,119.3	16,520.7
Acquired network location intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	5,930.6	5,981.5
Accumulated Amortization	(2,795.5)	(2,775.8)
Net Book Value	$ 3,135.1	$ 3,205.7
Acquired network location intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (years)	30 years	20 years
Acquired tenant-related intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 18,728.8	$ 18,894.5
Accumulated Amortization	(6,815)	(6,698.6)
Net Book Value	$ 11,913.8	12,195.9
Acquired tenant-related intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (years)	30 years
Acquired licenses and other intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 1,535.5	1,561.1
Accumulated Amortization	(465.1)	(442)
Net Book Value	$ 1,070.4	$ 1,119.1
Acquired licenses and other intangibles | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (years)	2 years
Acquired licenses and other intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (years)	30 years

GOODWILL AND OTHER INTANGIBLE_5

GOODWILL AND OTHER INTANGIBLE ASSETS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 242.5	$ 369.5
Weighted Average
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, remaining amortization period	20 years

GOODWILL AND OTHER INTANGIBLE_6

GOODWILL AND OTHER INTANGIBLE ASSETS - Expected Future Amortization Expenses (Details) $ in Millions	Mar. 31, 2024 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2024	$ 707.8
2025	921.9
2026	881.5
2027	869.5
2028	858
2029	$ 839

ACCRUED EXPENSES (Details)

ACCRUED EXPENSES (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Accrued Liabilities, Current [Abstract]
Accrued construction costs	$ 131.9	$ 183.8
Accrued income tax payable	26.9	21
Accrued pass-through costs	97	77.4
Amounts payable for acquisitions	1.9	27.7
Amounts payable to tenants	99.5	103.3
Accrued property and real estate taxes	294.5	295.5
Accrued rent	75.6	75.1
Payroll and related withholdings	98.2	147.4
Other accrued expenses	308.6	349.4
Total accrued expenses	$ 1,134.1	$ 1,280.6

LONG-TERM OBLIGATIONS - Long-Te

LONG-TERM OBLIGATIONS - Long-Term Debt Obligations (Details) € in Millions	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Mar. 07, 2024 USD ($)	Feb. 14, 2024 USD ($)	Jan. 12, 2024 USD ($)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Finance lease obligations	$ 19,800,000					$ 20,600,000
Total	39,259,500,000					38,921,500,000
Less current portion of long-term obligations	(3,067,600,000)					(3,187,500,000)
Long-term obligations	36,191,900,000					35,734,000,000
American Tower Corporation
Debt Instrument [Line Items]
Long-term debt	36,806,500,000					36,472,000,000
American Tower subsidiary
Debt Instrument [Line Items]
Long-term debt	2,433,200,000					2,428,900,000
2021 Multicurrency Credit Facility | Revolving Credit Facility | American Tower Corporation
Debt Instrument [Line Items]
Long-term debt	1,011,600,000					723,400,000
2021 Term Loan | Unsecured debt | American Tower Corporation
Debt Instrument [Line Items]
Long-term debt	997,200,000					997,000,000
2021 Credit Facility | Revolving Credit Facility | American Tower Corporation
Debt Instrument [Line Items]
Long-term debt	2,038,400,000					1,603,400,000
2021 EUR Three Year Delayed Draw Term Loan | Unsecured debt | American Tower Corporation
Debt Instrument [Line Items]
Long-term debt	$ 890,100,000	€ 825				910,700,000
0.600% Senior Notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	0.60%	0.60%			0.60%
Long-term debt	$ 0				$ 0	500,000,000
5.00% Senior Notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5%	5%		5%
Long-term debt	$ 0			$ 0		1,000,100,000
3.375% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.375%	3.375%
Long-term debt	$ 650,000,000					649,700,000
2.950% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.95%	2.95%
Long-term debt	$ 648,600,000					648,200,000
2.400% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.40%	2.40%
Long-term debt	$ 748,800,000					748,500,000
1.375% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.375%	1.375%
Long-term debt	$ 538,000,000					550,000,000
4.000% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	4%	4%
Long-term debt	$ 748,400,000					748,100,000
1.300% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.30%	1.30%
Long-term debt	$ 498,500,000					498,300,000
4.400% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	4.40%	4.40%
Long-term debt	$ 498,900,000					498,700,000
1.600% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.60%	1.60%
Long-term debt	$ 697,700,000					697,400,000
1.950% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.95%	1.95%
Long-term debt	$ 537,400,000					549,600,000
1.450% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.45%	1.45%
Long-term debt	$ 596,300,000					595,900,000
3.375% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.375%	3.375%
Long-term debt	$ 995,100,000					994,700,000
3.125% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.125%	3.125%
Long-term debt	$ 399,000,000					398,900,000
2.750% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.75%	2.75%
Long-term debt	$ 747,300,000					747,000,000
0.450% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	0.45%	0.45%
Long-term debt	$ 805,900,000					824,300,000
0.400% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	0.40%	0.40%
Long-term debt	$ 536,100,000					548,200,000
3.650% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.65%	3.65%
Long-term debt	$ 645,200,000					644,800,000
4.125% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	4.125%	4.125%
Long-term debt	$ 643,900,000					658,600,000
3.55% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.55%	3.55%
Long-term debt	$ 747,300,000					747,100,000
3.600% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.60%	3.60%
Long-term debt	$ 696,300,000					696,000,000
0.500% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	0.50%	0.50%
Long-term debt	$ 804,400,000					822,800,000
1.500% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.50%	1.50%
Long-term debt	$ 647,300,000					647,100,000
5.500% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.50%	5.50%
Long-term debt	$ 694,000,000					693,600,000
5.250% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.25%	5.25%
Long-term debt	$ 644,200,000					643,900,000
5.800% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.80%	5.80%
Long-term debt	$ 743,700,000					743,400,000
5.200% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.20%	5.20%	5.20%
Long-term debt	$ 642,700,000		$ 650,000,000			0
3.950% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.95%	3.95%
Long-term debt	$ 594,000,000					593,700,000
0.875% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	0.875%	0.875%
Long-term debt	$ 805,100,000					823,700,000
3.800% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.80%	3.80%
Long-term debt	$ 1,639,100,000					1,638,600,000
2.900% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.90%	2.90%
Long-term debt	$ 744,500,000					744,200,000
2.100% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.10%	2.10%
Long-term debt	$ 743,400,000					743,100,000
0.950% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	0.95%	0.95%
Long-term debt	$ 533,800,000					546,000,000
1.875% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.875%	1.875%
Long-term debt	$ 793,600,000					793,300,000
2.700% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.70%	2.70%
Long-term debt	$ 695,200,000					695,000,000
4.625% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	4.625%	4.625%
Long-term debt	$ 533,000,000					545,200,000
2.300% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.30%	2.30%
Long-term debt	$ 692,900,000					692,700,000
1.000% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1%	1%
Long-term debt	$ 695,400,000					711,500,000
4.050% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	4.05%	4.05%
Long-term debt	$ 643,100,000					642,900,000
5.650% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.65%	5.65%
Long-term debt	$ 790,800,000					790,600,000
1.250% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	1.25%	1.25%
Long-term debt	$ 533,400,000					545,800,000
5.550% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.55%	5.55%
Long-term debt	$ 840,800,000					840,600,000
5.900% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.90%	5.90%
Long-term debt	$ 741,700,000					741,500,000
5.450% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.45%	5.45%	5.45%
Long-term debt	$ 640,000,000		$ 650,000,000			0
3.700% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.70%	3.70%
Long-term debt	$ 592,500,000					592,400,000
3.100% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	3.10%	3.10%
Long-term debt	$ 1,038,600,000					1,038,600,000
2.950% senior notes | Senior Notes | American Tower Corporation
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.95%	2.95%
Long-term debt	$ 1,023,300,000					1,023,200,000
Series 2015-2 notes | Secured debt | American Tower subsidiary
Debt Instrument [Line Items]
Long-term debt	524,200,000					524,100,000
Series 2018-1A securities | Secured debt | American Tower subsidiary
Debt Instrument [Line Items]
Long-term debt	497,000,000					496,800,000
Series 2023-1A Securities | Secured debt | American Tower subsidiary
Debt Instrument [Line Items]
Long-term debt	1,285,300,000					1,284,400,000
Other subsidiary debt | Unsecured debt | American Tower subsidiary
Debt Instrument [Line Items]
Long-term debt	$ 126,700,000					$ 123,600,000

LONG-TERM OBLIGATIONS - Current

LONG-TERM OBLIGATIONS - Current Portion of Long-Term Obligations (Details) € in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Current portion of long-term obligations	$ 3,067.6		$ 3,187.5
Unsecured debt | 2021 EUR Three Year Delayed Draw Term Loan
Debt Instrument [Line Items]
Debt instrument term	3 years
American Tower Corporation | Senior Notes | 3.375% senior notes
Debt Instrument [Line Items]
Current portion of long-term obligations	$ 650
Debt interest rate (as a percent)	3.375%	3.375%
American Tower Corporation | Senior Notes | 2.950% senior notes
Debt Instrument [Line Items]
Current portion of long-term obligations	$ 650
Debt interest rate (as a percent)	2.95%	2.95%
American Tower Corporation | Senior Notes | 2.400% senior notes
Debt Instrument [Line Items]
Current portion of long-term obligations	$ 750
Debt interest rate (as a percent)	2.40%	2.40%
American Tower Corporation | Unsecured debt | 2021 EUR Three Year Delayed Draw Term Loan
Debt Instrument [Line Items]
Current portion of long-term obligations | €		€ 825
Debt instrument term	3 years

LONG-TERM OBLIGATIONS - Repayme

LONG-TERM OBLIGATIONS - Repayments of Senior Notes (Details) - American Tower Corporation - USD ($)	Feb. 14, 2024	Jan. 12, 2024	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Long-term debt			$ 36,806,500,000	$ 36,472,000,000
0.600% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)		0.60%	0.60%
Aggregate principal amount		$ 500,000,000
Long-term debt		$ 0	$ 0	500,000,000
5.00% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5%		5%
Aggregate principal amount	$ 1,000,000,000
Long-term debt	$ 0		$ 0	$ 1,000,100,000

LONG-TERM OBLIGATIONS - Offerin

LONG-TERM OBLIGATIONS - Offerings of Senior Notes (Details) - USD ($) $ in Millions		3 Months Ended
	Mar. 07, 2024	Mar. 31, 2024	Mar. 31, 2023
Debt Instrument [Line Items]
Proceeds from issuance of senior long-term debt		$ 1,293	$ 1,494.2
Redemption price percentage		101%
Senior Notes
Debt Instrument [Line Items]
Redemption price percentage		100%
American Tower Corporation | Senior Notes | 5.200% senior notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.20%	5.20%
Debt face amount	$ 650
American Tower Corporation | Senior Notes | 5.450% senior notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.45%	5.45%
Debt face amount	$ 650
American Tower Corporation | Senior Notes | 5.200% Senior Notes Due 2029 And 5.450% Senior Notes Due 2034
Debt Instrument [Line Items]
Proceeds from issuance of senior long-term debt	$ 1,281.3

LONG-TERM OBLIGATIONS - Key Ter

LONG-TERM OBLIGATIONS - Key Terms of Notes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 07, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Redemption price percentage	101%
Senior Notes
Debt Instrument [Line Items]
Redemption price percentage	100%
American Tower Corporation
Debt Instrument [Line Items]
Long-term debt	$ 36,806.5		$ 36,472
American Tower Corporation | Senior Notes | 5.200% senior notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.20%	5.20%
Long-term debt	$ 642.7	$ 650	0
American Tower Corporation | Senior Notes | 5.450% senior notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)	5.45%	5.45%
Long-term debt	$ 640	$ 650	$ 0

LONG-TERM OBLIGATIONS - Bank Fa

LONG-TERM OBLIGATIONS - Bank Facilities (Details) € in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Mar. 31, 2023 USD ($)	Feb. 14, 2024	Jan. 12, 2024
Line of Credit Facility [Line Items]
Borrowings under credit facilities	$ 2,790.5		$ 1,745
0.600% Senior Notes | American Tower Corporation | Senior Notes
Line of Credit Facility [Line Items]
Debt interest rate (as a percent)	0.60%				0.60%
5.00% Senior Notes | American Tower Corporation | Senior Notes
Line of Credit Facility [Line Items]
Debt interest rate (as a percent)	5%			5%
Revolving Credit Facility | 2021 Multicurrency Credit Facility | American Tower Corporation
Line of Credit Facility [Line Items]
Borrowings under credit facilities	$ 2,000
Repayment of indebtedness under credit facility	1,700
Line of credit maximum borrowing capacity	6,000
Revolving Credit Facility | 2021 Multicurrency Credit Facility In Euros | American Tower Corporation
Line of Credit Facility [Line Items]
Borrowings under credit facilities	339.4	€ 315
Repayment of indebtedness under credit facility	91.9	€ 85
Revolving Credit Facility | 2021 Credit Facility | American Tower Corporation
Line of Credit Facility [Line Items]
Borrowings under credit facilities	775
Repayment of indebtedness under credit facility	340
Line of credit maximum borrowing capacity	$ 4,000

LONG-TERM OBLIGATIONS - Credit

LONG-TERM OBLIGATIONS - Credit Facilities and Term Loans (Details) € in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) renewalPeriod	Mar. 31, 2024 EUR (€)	Dec. 31, 2023 USD ($)
2021 EUR Three Year Delayed Draw Term Loan | Unsecured debt
Line of Credit Facility [Line Items]
Debt instrument term	3 years
American Tower Corporation
Line of Credit Facility [Line Items]
Long-term debt	$ 36,806.5		$ 36,472
American Tower Corporation | Revolving Credit Facility
Line of Credit Facility [Line Items]
Number of optional renewal periods | renewalPeriod	2
American Tower Corporation | 2021 Multicurrency Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt	$ 1,011.6		723.4
Outstanding principal balance	1,011.6
Undrawn letters of credit	$ 3.5
Current commitment fee, percentage	0.11%
American Tower Corporation | 2021 Multicurrency Credit Facility | Revolving Credit Facility | SOFR
Line of Credit Facility [Line Items]
Current margin over LIBOR or EURIBOR	1.125%
American Tower Corporation | 2021 Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt	$ 2,038.4		1,603.4
Outstanding principal balance	2,038.4
Undrawn letters of credit	$ 30.4
Current commitment fee, percentage	0.11%
American Tower Corporation | 2021 Credit Facility | Revolving Credit Facility | SOFR
Line of Credit Facility [Line Items]
Current margin over LIBOR or EURIBOR	1.125%
American Tower Corporation | 2021 Term Loan | Unsecured debt
Line of Credit Facility [Line Items]
Long-term debt	$ 997.2		997
Outstanding principal balance	$ 1,000
American Tower Corporation | 2021 Term Loan | Unsecured debt | SOFR
Line of Credit Facility [Line Items]
Current margin over LIBOR or EURIBOR	1.125%
American Tower Corporation | 2021 EUR Three Year Delayed Draw Term Loan | Unsecured debt
Line of Credit Facility [Line Items]
Long-term debt	$ 890.1	€ 825	$ 910.7
Debt instrument term	3 years
Outstanding principal balance	$ 890.2
American Tower Corporation | 2021 EUR Three Year Delayed Draw Term Loan | Unsecured debt | EURIBOR
Line of Credit Facility [Line Items]
Current margin over LIBOR or EURIBOR	1.125%

FAIR VALUE MEASUREMENTS - Asset

FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) $ in Millions, ₨ in Billions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Mar. 23, 2024 USD ($)	Mar. 23, 2024 INR (₨)	Dec. 31, 2023 USD ($)
Assets:
Unrealized (losses) gains on equity securities	$ (14.7)	$ 1.2
VIL
Assets:
Investments in equity securities	172.7
OCDs | VIL
Assets:
Debt securities			$ 172.7	₨ 14.4
Fair Value, Measurements, Recurring | Level 1
Assets:
Investments in equity securities	13.5				$ 28.2
Fair Value, Measurements, Recurring | Level 1 | VIL
Assets:
Investments in equity securities	0				0
Fair Value, Measurements, Recurring | Level 1 | OCDs | VIL
Assets:
Debt securities	0				0
Fair Value, Measurements, Recurring | Level 2
Assets:
Investments in equity securities	5.3				5.3
Fair Value, Measurements, Recurring | Level 2 | VIL
Assets:
Investments in equity securities	172.7				0
Fair Value, Measurements, Recurring | Level 2 | OCDs | VIL
Assets:
Debt securities	19.2				192.3
Fair Value, Measurements, Recurring | Level 3
Assets:
Investments in equity securities	0				0
Fair Value, Measurements, Recurring | Level 3 | VIL
Assets:
Investments in equity securities	0				0
Fair Value, Measurements, Recurring | Level 3 | OCDs | VIL
Assets:
Debt securities	$ 0				$ 0

FAIR VALUE MEASUREMENTS - Narra

FAIR VALUE MEASUREMENTS - Narrative (Details) shares in Millions, $ in Millions, ₨ in Billions				3 Months Ended
	Apr. 29, 2024 USD ($)	Apr. 29, 2024 INR (₨)	Mar. 23, 2024 USD ($) shares	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Mar. 23, 2024 INR (₨)	Dec. 31, 2023 USD ($)	Feb. 28, 2023 USD ($)	Feb. 28, 2023 INR (₨)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Asset impairments				$ 0	$ 0
Long-term obligations				39,259.5			$ 38,921.5
VIL
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Number of converted shares | shares			1,440
Investments in equity securities				172.7
Subsequent Event | VIL
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Net proceeds	$ 216	₨ 18
Level 1 | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments in equity securities				13.5			28.2
Level 1 | VIL | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments in equity securities				0			0
Level 2 | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments in equity securities				5.3			5.3
Level 2 | VIL | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments in equity securities				172.7			0
Estimate of Fair Value Measurement
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, fair value				36,800			36,700
Estimate of Fair Value Measurement | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, fair value				29,400			30,000
Estimate of Fair Value Measurement | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, fair value				7,400			6,700
OCDs | VIL
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt securities			$ 172.7			₨ 14.4
OCDs | Level 1 | VIL | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt securities				0			0
OCDs | Level 2 | VIL | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt securities				$ 19.2			$ 192.3
OCDs | VIL
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
VIL OCDs, face value								$ 193.2	₨ 16
Debt securities								$ 116.5
Debt securities, interest rate (as a percent)								11.20%	11.20%
OCDs | VIL | Maturing on August 27, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
VIL OCDs, face value								$ 96.6	₨ 8
OCDs | VIL | Maturing on August 27, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
VIL OCDs, face value								$ 96.6	₨ 8

INCOME TAXES - Narrative (Detai

INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Income Tax Contingency [Line Items]
Unrecognized tax benefits that would impact the ETR	$ 132.1	$ 130.7
Unrecognized tax benefits, increase resulting from current period tax positions	1
Unrecognized tax benefits, increase resulting from foreign currency translation	0.4
Unrecognized tax benefits, income tax penalties and interest accrued	67.3	$ 62.8
Minimum
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	0
Maximum
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 14.3

INCOME TAXES - Penalties and In

INCOME TAXES - Penalties and Income Tax Related Expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Penalties and income tax-related interest expense	$ 5.5	$ 2.8

STOCK-BASED COMPENSATION - Narr

STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended
	Mar. 09, 2023	Dec. 31, 2022	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount from market price (in percent)			15%
Stock-based compensation expense			$ 64.9	$ 65.5
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issuable under stock incentive plan (in shares)			3,300,000
Stock Options and Time-Based Restricted Stock Units | 2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years	3 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Unrecognized compensation expense			$ 22.7
Expected weighted average recognition period			2 years
Units granted (in shares)			87,550
Stock-based compensation expense			$ 9.1
Performance Shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares			0%
Performance Shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares			200%
Performance Shares | 2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Performance Shares | 2024 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares)			87,550
Weighted average grant date fair value (in dollars per share)			$ 216.11
Performance Shares | 2023 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares)					118,684
Performance Shares | 2022 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares)						98,542
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 0
Stock Options | 2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period			10 years
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares)			688,313
Restricted stock units | 2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 258.1
Restricted stock units | 2007 Plan | Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted average recognition period			2 years

STOCK-BASED COMPENSATION - Stoc

STOCK-BASED COMPENSATION - Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-based compensation expense	$ 64.9	$ 65.5

STOCK-BASED COMPENSATION - Comp

STOCK-BASED COMPENSATION - Company's Option Activity (Details)	3 Months Ended
	Mar. 31, 2024 shares
Number of Options
Outstanding at beginning of period (in shares)	766,955
Exercised (in shares)	(166,886)
Forfeited (in shares)	0
Expired (in shares)	0
Outstanding at end of period (in shares)	600,069

STOCK-BASED COMPENSATION - Fair

STOCK-BASED COMPENSATION - Fair Value of the TSR (Details) - PSUs - 2024 PSUs	3 Months Ended
	Mar. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	2 years 9 months 21 days
Risk-free interest rate	4.31%
Annualized volatility	26.75%

STOCK-BASED COMPENSATION - Rest

STOCK-BASED COMPENSATION - Restricted Stock Activity (Details) - shares	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units outstanding at beginning of period (in shares)	1,638,711
Units granted (in shares)	688,313
Units vested and released (in shares)	(639,358)
Units forfeited (in shares)	(8,510)
Units outstanding at end of period (in shares)	1,679,156	1,638,711
Units vested and deferred (in shares)	8,502
PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units outstanding at beginning of period (in shares)	363,488
Units granted (in shares)	87,550
Units vested and released (in shares)	(97,124)
Units forfeited (in shares)	(1,337)
Units outstanding at end of period (in shares)	352,577	363,488
Units vested and deferred (in shares)	21,961
PSUs | 2023 PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units granted (in shares)		118,684
Units outstanding at end of period (in shares)	118,684
Performance period	3 years
PSUs | 2022 PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units granted (in shares)			98,542
Units outstanding at end of period (in shares)	98,542
Performance period	3 years
PSUs | 2021 PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units outstanding at end of period (in shares)	127,318
Performance period	3 years
Remaining shares vested and expected to vest, outstanding (in shares)	8,233
PSUs | Retention PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units granted (in shares)	18,944
Performance period	1 year
PSUs | 2024 PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Units granted (in shares)	87,550
Performance period	3 years

EQUITY - Narrative (Details)

EQUITY - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2017	Mar. 31, 2011
Class of Stock [Line Items]
Proceeds from stock options	$ 13.9
Number of shares repurchased (in shares)	0
Treasury stock, shares (in shares)	11,004,000		11,004,000
Treasury stock repurchased amount	$ 1,301.2		$ 1,301.2
Accrued dividend RSU	15.4
Paid dividend RSU	$ 9.4	$ 6.6
2011 Buyback
Class of Stock [Line Items]
Stock repurchase program, authorized amount					$ 1,500
Treasury stock, shares (in shares)	14,451,325
Treasury stock repurchased amount	$ 1,500
2017 Buyback
Class of Stock [Line Items]
Stock repurchase program, authorized amount				$ 2,000
Treasury stock activity (in shares)	0

EQUITY - Distributions (Details

EQUITY - Distributions (Details) - USD ($) $ / shares in Units, $ in Millions									3 Months Ended
	Apr. 26, 2024	Mar. 14, 2024	Feb. 01, 2024	Dec. 13, 2023	Apr. 28, 2023	Mar. 08, 2023	Feb. 02, 2023	Dec. 07, 2022	Mar. 31, 2024	Mar. 31, 2023
Dividends Payable [Line Items]
Aggregate payment amount on common stock									$ 802.1	$ 733.6
Dividends Declared and Paid | Common Stock
Dividends Payable [Line Items]
Distribution per share (in dollars per share)		$ 1.62		$ 1.70		$ 1.56		$ 1.56
Aggregate payment amount on common stock			$ 792.7		$ 727		$ 726.3
Dividends Declared and Paid | Common Stock | Subsequent Event
Dividends Payable [Line Items]
Aggregate payment amount on common stock	$ 756.5

NONCONTROLLING INTERESTS - Narr

NONCONTROLLING INTERESTS - Narrative (Details) € in Millions, ৳ in Millions, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended			48 Months Ended
	Aug. 31, 2022	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 BDT (৳)	Dec. 31, 2021 USD ($)	Aug. 31, 2026
U.S. | Data Centers
Noncontrolling Interest [Line Items]
Stock conversion period	4 years
U.S. | Data Centers | Common Stock
Noncontrolling Interest [Line Items]
Percentage of ownership after transaction (as a percent)		72%	72%
U.S. | Data Centers | Common Stock | Forecast
Noncontrolling Interest [Line Items]
Percentage of ownership after transaction (as a percent)							64%
Kirtonkhola Tower Bangladesh Limited
Noncontrolling Interest [Line Items]
Percentage of interests acquired (as a percent)					51%	51%
Business combination, consideration transferred					৳ 900	$ 10.6
Stonepeak
Noncontrolling Interest [Line Items]
Dividends, preferred stock		$ 11.5
Dividends, common stock		91.7
Noncash dividends		37.5
Stonepeak | Preferred Stock
Noncontrolling Interest [Line Items]
Accrued dividends		11.5
Stonepeak | U.S. | Data Centers
Noncontrolling Interest [Line Items]
Payments to acquire noncontrolling interest				$ 3,100
AT Europe Cv
Noncontrolling Interest [Line Items]
Dividends		183.2	€ 170
AT Iberia Cv
Noncontrolling Interest [Line Items]
Dividends		$ 48.6	€ 45
ATC Europe
Noncontrolling Interest [Line Items]
Noncontrolling ownership interest percentage (as a percent)		52%
ATC Europe | CDPQ
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)		30%
ATC Europe | Allianz
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)		18%
France | ATC Europe
Noncontrolling Interest [Line Items]
Noncontrolling ownership interest percentage (as a percent)		100%
Germany
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)		13%
Germany | ATC Europe
Noncontrolling Interest [Line Items]
Noncontrolling ownership interest percentage (as a percent)		87%
Ownership percentage by noncontrolling owners (as a percent)		87%
Spain
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)		17%
Spain | ATC Europe
Noncontrolling Interest [Line Items]
Noncontrolling ownership interest percentage (as a percent)		83%
Kirtonkhola Tower Bangladesh Limited | Confidence Group
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)					49%	49%
Stonepeak | U.S. | Data Centers
Noncontrolling Interest [Line Items]
Preferred stock, dividend rate (as a percent)		5%	5%
Preferred stock, conversion ratio		1
Stonepeak | U.S. | Data Centers | Common Stock
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)		28%
Stonepeak | U.S. | Data Centers | Common Stock | Forecast
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)							36%
Stonepeak | U.S. | Data Centers | Preferred Stock
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners (as a percent)		100%

NONCONTROLLING INTERESTS - Chan

NONCONTROLLING INTERESTS - Changes in Noncontrolling Interest (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	$ 10,865.4	$ 12,408.5
Net income (loss) attributable to noncontrolling interests	921.7	315
Contributions from noncontrolling interest holders	138.9
Distributions to noncontrolling interest holders	(103.8)	(11.5)
Balance at end of period	10,661.7	12,250.3
Stonepeak
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Noncash dividends	37.5
Stonepeak
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Contributions from noncontrolling interest holders	137.3
Noncontrolling Interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	6,667.2	6,836.1
Net income (loss) attributable to noncontrolling interests	4.3	(20.8)
Foreign currency translation adjustment attributable to noncontrolling interests, net of tax	(92.7)	39.9
Contributions from noncontrolling interest holders	138.9
Distributions to noncontrolling interest holders	(103.8)	(11.5)
Balance at end of period	6,613.9	6,843.7
Noncontrolling Interests | All Other Entities
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Contributions from noncontrolling interest holders	$ 138.9	$ 0

EARNINGS PER COMMON SHARE - Ear

EARNINGS PER COMMON SHARE - Earnings Per Basic and Diluted by Common Class (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net income attributable to American Tower Corporation common stockholders, basic	$ 917.4	$ 335.8
Net income attributable to American Tower Corporation common stockholders, diluted	$ 917.4	$ 335.8
Basic weighted average common shares outstanding (in shares)	466,519	465,741
Dilutive securities (in shares)	1,141	1,069
Diluted weighted average common shares outstanding (in shares)	467,660	466,810
Basic net income attributable to American Tower Corporation common stockholders per common share (in dollars per share)	$ 1.97	$ 0.72
Diluted net income attributable to American Tower Corporation common stockholders per common share (in dollars per share)	$ 1.96	$ 0.72

EARNINGS PER COMMON SHARE - Sha

EARNINGS PER COMMON SHARE - Shares Excluded From Computation Of Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from dilutive effect (in shares)	126	5

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details) $ in Billions		3 Months Ended
	Mar. 27, 2015 USD ($) communicationsSite renewalPeriod	Mar. 31, 2024 USD ($) communicationsSite renewalPeriod	Dec. 31, 2000 communicationsSite
Verizon Transaction
Loss Contingencies [Line Items]
Leased assets, number of communication sites | communicationsSite	11,200
Right to lease, weighted average term	28 years
Aggregate purchase option price for towers | $	$ 5
Customer lease, initial term	10 years
Successive terms to renew lease | renewalPeriod	8
Lease renewal term	5 years
AT&T Transaction
Loss Contingencies [Line Items]
Leased assets, number of communication sites | communicationsSite		600	1,800
Aggregate purchase option price for towers | $		$ 1.1
Successive terms to renew lease | renewalPeriod		5
Lease renewal term		5 years
Operating lease, term of contract		27 years

BUSINESS SEGMENTS - Summarized

BUSINESS SEGMENTS - Summarized Segment Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Segment Reporting Information [Line Items]
Segment revenues	$ 2,834.1	$ 2,767.2
Segment selling, general, administrative and development expense	257	263.9
OPERATING INCOME	1,236.6	775.6
Stock-based compensation expense	64.9	65.5
Other selling, general, administrative and development expense	62.1	59.9
Depreciation, amortization and accretion	549.4	794.1
Other expense	208.5	534.7
Income from continuing operations before income taxes	1,030.9	368.4
Total assets	66,679	66,817.7	$ 66,027.6
Impairment charges		29.8
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Mexico Fiber
Segment Reporting Information [Line Items]
Gain (loss) on sale		(80)
U.S. & Canada
Segment Reporting Information [Line Items]
Segment revenues	1,340.9	1,340.3
Asia-Pacific
Segment Reporting Information [Line Items]
Segment revenues	326.6	251.1
Africa
Segment Reporting Information [Line Items]
Segment revenues	292	317
Europe
Segment Reporting Information [Line Items]
Segment revenues	204.5	191.7
Latin America
Segment Reporting Information [Line Items]
Segment revenues	445.5	464.1
Data Centers
Segment Reporting Information [Line Items]
Segment revenues	224.6	203
Operating Segments
Segment Reporting Information [Line Items]
Segment revenues	2,834.1	2,767.2
Segment operating expenses	788.3	806.1
Segment gross margin	2,045.8	1,961.1
Segment selling, general, administrative and development expense	130	138.5
OPERATING INCOME	1,915.8	1,822.6
Operating Segments | Property
Segment Reporting Information [Line Items]
Segment revenues	2,803.9	2,714.5
Segment operating expenses	774.4	787
Segment gross margin	2,029.5	1,927.5
Segment selling, general, administrative and development expense	125.1	132.8
OPERATING INCOME	1,904.4	1,794.7
Total assets	65,902	66,152.5
Operating Segments | U.S. & Canada
Segment Reporting Information [Line Items]
Segment revenues	1,310.7	1,287.6
Segment operating expenses	204.3	205.3
Segment gross margin	1,106.4	1,082.3
Segment selling, general, administrative and development expense	36.6	40.8
OPERATING INCOME	1,069.8	1,041.5
Total assets	26,879	26,657.4
Operating Segments | Asia-Pacific
Segment Reporting Information [Line Items]
Segment revenues	326.6	251.1
Segment operating expenses	170.7	168.4
Segment gross margin	155.9	82.7
Segment selling, general, administrative and development expense	12.8	8.8
OPERATING INCOME	143.1	73.9
Total assets	3,821.9	3,879.7
Operating Segments | Africa
Segment Reporting Information [Line Items]
Segment revenues	292	317
Segment operating expenses	92.7	118.5
Segment gross margin	199.3	198.5
Segment selling, general, administrative and development expense	14.9	21.4
OPERATING INCOME	184.4	177.1
Total assets	3,972.3	4,632.4
Operating Segments | Europe
Segment Reporting Information [Line Items]
Segment revenues	204.5	191.7
Segment operating expenses	73.5	73.1
Segment gross margin	131	118.6
Segment selling, general, administrative and development expense	15.8	14.6
OPERATING INCOME	115.2	104
Total assets	11,676	11,609.5
Operating Segments | Latin America
Segment Reporting Information [Line Items]
Segment revenues	445.5	464.1
Segment operating expenses	140.3	137.9
Segment gross margin	305.2	326.2
Segment selling, general, administrative and development expense	27.8	29.7
OPERATING INCOME	277.4	296.5
Total assets	9,097.7	8,741
Operating Segments | Data Centers
Segment Reporting Information [Line Items]
Segment revenues	224.6	203
Segment operating expenses	92.9	83.8
Segment gross margin	131.7	119.2
Segment selling, general, administrative and development expense	17.2	17.5
OPERATING INCOME	114.5	101.7
Total assets	10,455.1	10,632.5
Operating Segments | Services
Segment Reporting Information [Line Items]
Segment revenues	30.2	52.7
Segment operating expenses	13.9	19.1
Segment gross margin	16.3	33.6
Segment selling, general, administrative and development expense	4.9	5.7
OPERATING INCOME	11.4	27.9
Total assets	67.4	125.2
Other
Segment Reporting Information [Line Items]
Stock-based compensation expense	64.9	65.5
Other selling, general, administrative and development expense	62.1	59.9
Depreciation, amortization and accretion	549.4	794.1
Other expense	208.5	534.7
Total assets	$ 709.6	$ 540

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - Apr. 29, 2024 - Subsequent Event - VIL ₨ / shares in Units, $ in Millions, ₨ in Billions	USD ($)	INR (₨) ₨ / shares
Subsequent Event [Line Items]
Price per share (in INR per share)		₨ 12.78
Proceeds from issuance of stock	$ 216	₨ 18