v3.25.4

BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Sale of South Africa Fiber, Narrative (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations - South Africa Fiber $ in Millions, R in Billions		12 Months Ended
	Mar. 06, 2025 USD ($)	Dec. 31, 2025 USD ($)	Mar. 06, 2025 ZAR (R)	Mar. 06, 2025 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds received at closing			R 2.5	$ 137.7
Gain on sale of subsidiary	$ 53.6	$ 53.6
Goodwill disposed due to sale of subsidiary	$ 6.1

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
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Amount of divestiture of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
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AMERICAN TOWER CORP /MA/ 10-K