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DISCONTINUED OPERATIONS - Cash Flow and Non-Cash Information Related to Discontinued Operations (Details) - Discontinued Operations, Disposed of by Sale - ATC TIPL - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |
Capital expenditures | $ 0.0 | $ (26.2)
Significant non-cash items: |  |
Depreciation, amortization and accretion | 0.0 | 40.6
Stock-based compensation expense | 0.0 | 2.1
Impairments, net loss on sale of long-lived assets, non-cash restructuring and merger related expenses | 0.0 | (1.6)
Loss (gain) on investments, unrealized foreign currency loss (gain) and other non-cash expense | $ 0.0 | $ 0.5

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