SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Supplemental Cash Flow Information [Abstract]
Cash paid for interest, net of amount capitalized	$ 318.3	$ 324.1
Cash paid for income taxes, net	59.4	71.0
Significant non-cash investing and financing transactions:
Accounts payable related to construction costs	29.7	38.1
Increase in receivable related to insurance proceeds for property damage (1)	58.3	0.0
Receivable from a related party related to insurance proceeds for property damage (1)	$ 0.0	$ 20.0

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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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Receivable from a related party related to insurance proceeds for property damage

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The amount of a receivable related to insurance proceeds for property damage considered to be a noncash investing or financing activity.

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