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CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES - Toggle Senior Secured Exchangeable Notes due 2030 (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jul. 01, 2025
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Total principal amount of corporate borrowings	$ 4,024.2	$ 4,024.2	$ 4,134.5
Discount	(68.5)	(68.5)	(171.3)
Debt issuance costs	(64.4)	(64.4)	(47.2)
Accrued paid-in-kind interest	2.7	2.7	1.5
Total	4,024.2	4,024.2
Discount, (increase) decrease to net earnings (loss)		14.6	(17.5)	$ (55.6)
Deferred issuance cost, (increase) decrease to net earnings (loss)		11.3	8.3	9.6
Change in fair value of derivative		(37.4)	(75.8)
Carrying value of the debt extinguished			(418.2)	$ (376.1)
6.00%/8.00% Cash/PIK Toggle Senior Secured Exchangeable Notes due 2030
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Total principal amount of corporate borrowings	111.6	111.6	427.6		$ 337.4
Discount	(26.4)	(26.4)	(117.9)
Debt issuance costs	(5.2)	(5.2)	(23.3)		(17.1)
Accrued paid-in-kind interest	0.4	0.4	1.5
Bifurcated embedded derivative	12.6	12.6	157.6		88.3
Total	$ 93.0	93.0	445.5		322.4
Principal balance, (increase) decrease to net earnings (loss)		21.4
Discount, (increase) decrease to net earnings (loss)		5.0
Deferred issuance cost, (increase) decrease to net earnings (loss)		1.0
Accrued paid-in-kind interest, (increase) decrease to net earnings (loss)		0.1
Change in fair value of derivative		(56.7)	$ (75.8)
Carrying value, (Increase) Decrease to Net Earnings (Loss)		(29.2)
Carrying value of the debt extinguished		(337.4)
Discount		86.5
Debt issuance costs		17.1
Accrued paid-in-kind interest		(1.2)
Bifurcated embedded derivative		(88.3)
Carrying value		$ (323.3)
Effective interest rate	15.12%	15.12%
Senior Secured Exchangeable Notes due 2030
CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES
Total principal amount of corporate borrowings	$ 155.8	$ 155.8			194.4
Discount	(57.4)	(57.4)			(35.4)
Debt issuance costs	(14.8)	(14.8)			(6.4)
Bifurcated embedded derivative	131.9	131.9			41.7
Total	215.5	215.5			$ 194.3
Principal balance, (increase) decrease to net earnings (loss)	1.3
Discount, (increase) decrease to net earnings (loss)	2.7
Deferred issuance cost, (increase) decrease to net earnings (loss)	0.5
Change in fair value of derivative	19.3	$ 19.3
Carrying value, (Increase) Decrease to Net Earnings (Loss)	23.8
Principal balance, Principal Cancellation & Interest Adjustment Features	(39.9)
Discount, Principal Cancellation & Interest Adjustment Features	(24.7)
Bifurcated embedded derivative, Principal Cancellation & Interest Adjustment Features	64.6
Carrying value, Principal Cancellation & Interest Adjustment Features	0.0
Debt issuance costs, Additional Deferred Charges	(8.9)
Bifurcated embedded derivative, Additional Deferred Charges	6.3
Carrying value, Additional Deferred Charges	$ (2.6)
Effective interest rate	17.00%	17.00%