Fresh-Start Accounting - Reorganization Items (Details) - USD ($) $ in Millions			1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Nov. 14, 2023	Jun. 16, 2022	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 27, 2024
Reorganization, Chapter 11 [Line Items]
Cash Paid, Reorganization items			$ 0.8	$ 18.4	$ 304.1	$ 22.6
Debtor Reorganization Items, Legal and Advisory Professional Fees			4.0	23.2	161.1	61.7
Debtor Reorganization Items, Success Fees			0.0	0.0	44.3	0.0
Debtor Reorganization Items, Net, Prepaid Expense Write-Off			0.0	0.0	9.2	20.0
Debtor Reorganization Items, Acceleration of Predecessor Equity Awards			0.0	0.0	0.0	9.0
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts			0.0	0.0	0.0	21.2
Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net			0.0	0.0	5.4	1,139.5
Reorganization items, net			4.0	23.2	630.9	892.7	$ 0.0
Debtor Reorganization Items, Debt Financing			0.0	0.0	0.0	154.6
Reorganization, Chapter 11, Plan Effect Adjustment
Reorganization, Chapter 11 [Line Items]
Gain on settlement of liabilities subject to compromise	$ 1,966.0	$ 943.7	0.0	0.0	(943.7)	(1,966.0)
Reorganization, Chapter 11, Fresh-Start Adjustment
Reorganization, Chapter 11 [Line Items]
Reorganization Items, net, Loss on Fresh-Start Adjustments	$ (1,452.7)	$ (1,354.6)	$ 0.0	$ 0.0	$ 1,354.6	$ 1,452.7