SUPPLEMENTAL CASH FLOW INFORMATION - SUPPLEMENTAL INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Supplemental cash flow information
Cash paid for interest, net of amount capitalized	$ 158.6	$ 107.5
Cash paid (received) for income taxes, net	(83.0)	1.0
Cash received from sale of production tax credits	83.4
Significant non-cash investing and financing transactions
Accounts payable related to construction costs	147.2	123.0
Common stock issued for stock-based compensation plans	6.2	0.0
Increase in receivables related to insurance proceeds	$ 0.0	$ 20.7

Future cash outflow to pay for purchases of fixed assets that have occurred.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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