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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Millions, R in Billions |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Mar. 06, 2025 USD ($) | Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($) | Jun. 30, 2025 USD ($) segment | Jun. 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 |  | $ 28.2 | $ 74.1 | $ 45.3 | $ 153.2 |  |
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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