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GOODWILL AND OTHER INTANGIBLE ASSETS - Other Intangible Assets Subject to Amortization (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
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Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Value | $ 24,828.9 | $ 24,438.2
Accumulated Amortization | (10,186.4) | (9,963.9)
Net Book Value | 14,642.5 | 14,474.3
Acquired network location intangibles |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Value | 5,452.5 | 5,365.4
Accumulated Amortization | (2,696.7) | (2,659.8)
Net Book Value | $ 2,755.8 | 2,705.6
Acquired network location intangibles | Maximum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated Useful Lives (years) | 30 years |
Acquired tenant-related intangibles |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Value | $ 17,987.1 | 17,666.0
Accumulated Amortization | (6,989.9) | (6,823.7)
Net Book Value | $ 10,997.2 | 10,842.3
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 | $ 1,389.3 | 1,406.8
Accumulated Amortization | (499.8) | (480.4)
Net Book Value | $ 889.5 | $ 926.4
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 |

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