SUPPLEMENTAL CASH FLOW INFORMATION - ADDITIONAL INFORMATION (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025
Supplemental cash flow information
Cash paid for interest, net of amount capitalized	$ 581.2	$ 555.4
Significant non-cash investing and financing transactions
Accounts payable related to construction costs	338.3	227.6
Common stock issued for stock-based compensation plans	4.2	3.2
Liabilities accrued for software licensing agreements	2.6	20.7
(Decrease) increase in receivables related to property damage insurance proceeds	$ (0.5)	$ 2.5

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-3

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 25
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-25

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-2

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The fair value of stock issued in noncash financing activities.

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Future cash outflow to pay for software licensing agreements already signed and considered to be a noncash investing or financing activity.

+ References

No definition available.

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Increase (decrease) in the receivables related to insurance proceeds for property damage considered to be a noncash investing or financing activity.

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No definition available.

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