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CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES - 2024 Extinguishments (Details) - USD ($) $ in Millions				12 Months Ended
	Aug. 06, 2025	Jul. 07, 2025	Jul. 01, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Nov. 08, 2016
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Fair value of Common Stock issued			$ 225.0
Cash paid for interest			0.3
Total consideration			425.7
Carrying value of corporate borrowings				$ 4,024.2	$ 4,134.5
Debt issuance costs				(64.4)	(47.2)
Carrying value				4,024.2
(Gain)/Loss on extinguishment of debt				196.0	(38.9)	$ (142.8)
Term Loan modifications - third party fees	$ 3.1			3.1	42.3
Senior Secured Exchangeable Notes due 2030
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Corporate borrowings, fair value			159.0
Derivative liability - Conversion Option			41.7	131.9
Carrying value of corporate borrowings			194.4	155.8
Debt issuance costs			(6.4)	(14.8)
Carrying value			194.3	215.5
6.00%/8.00% Cash/PIK Toggle Senior Secured Exchangeable Notes due 2030
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Derivative liability - Conversion Option			88.3	12.6	157.6
Carrying value of corporate borrowings			337.4	111.6	427.6
Discount			(86.5)
Debt issuance costs			(17.1)	(5.2)	(23.3)
Carrying value			322.4	93.0	$ 445.5
(Gain)/Loss on extinguishment of debt			103.3	103.3
Senior Secured Notes due 2029
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Corporate borrowings, fair value			925.4
Gross proceeds			(244.4)
Cash fee paid			2.4
Total consideration			683.4
Carrying value of corporate borrowings				$ 877.1
Existing 7.5% Notes Indenture
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Stated interest rate (as a percent)				7.50%	7.50%
Carrying value of corporate borrowings			590.0	$ 360.0	$ 950.0
Debt issuance costs			(5.6)
Carrying value			584.4
(Gain)/Loss on extinguishment of debt			$ 99.0	$ 99.0
Second Lien Subordinated Notes due 2026
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Cash fee paid					2.3
Carrying value of corporate borrowings					131.2
Carrying value					574.6
(Gain)/Loss on extinguishment of debt	(6.6)				61.2
Term Loan modifications - third party fees					$ 42.3
5.875% Senior Subordinated Notes due 2026
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Stated interest rate (as a percent)					5.875%		5.875%
Carrying value of corporate borrowings					$ 41.9
(Gain)/Loss on extinguishment of debt	$ 0.3
Subordinated debt
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Debt instrument redemption amount as a percentage of principal amount		100.00%