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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Millions, R in Billions		3 Months Ended		9 Months Ended
	Mar. 06, 2025 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) segment	Sep. 30, 2024 USD ($)	Mar. 06, 2025 ZAR (R)	Mar. 06, 2025 USD ($)
Accounting Policies [Line Items]
Number of reportable segments | segment				6
Property straight-line revenue		$ 27.7	$ 68.5	$ 73.0	$ 221.7
Disposal Group, Disposed of by Sale, Not Discontinued Operations | South Africa Fiber
Accounting Policies [Line Items]
Total consideration received upon disposal						R 2.5	$ 137.7
Gain on sale of subsidiary	$ 53.6			$ 53.6
Goodwill disposed due to sale of subsidiary	$ 6.1
U.S. | Data Centers | Common Stock
Accounting Policies [Line Items]
Percentage of ownership after transaction (as a percent)				71.00%
ATC Europe
Accounting Policies [Line Items]
Controlling ownership interest percentage (as a percent)		52.00%		52.00%
Joint Venture - Bangladesh Operations
Accounting Policies [Line Items]
Ownership percentage (as a percent)		51.00%		51.00%
Stonepeak | U.S. | Data Centers | Common Stock
Accounting Policies [Line Items]
Noncontrolling owner ownership percentage (as a percent)		29.00%		29.00%
Stonepeak | U.S. | Data Centers | Preferred stock
Accounting Policies [Line Items]
Noncontrolling owner ownership percentage (as a percent)		100.00%		100.00%
Germany
Accounting Policies [Line Items]
Noncontrolling owner ownership percentage (as a percent)		13.00%		13.00%
Germany | ATC Europe
Accounting Policies [Line Items]
Controlling ownership interest percentage (as a percent)		87.00%		87.00%
Spain
Accounting Policies [Line Items]
Noncontrolling owner ownership percentage (as a percent)		17.00%		17.00%
Spain | ATC Europe
Accounting Policies [Line Items]
Controlling ownership interest percentage (as a percent)		83.00%		83.00%

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