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Debt (Schedule of Long term debt) (Details) - USD ($) $ in Millions	Jun. 16, 2022	Dec. 30, 2022	Dec. 31, 2021
Long-term Debt, Current Maturities [Abstract]
Long-term Debt, Current Maturities		$ (44.1)	$ (1,395.0)
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross		3,048.5	0.0
Debt Issuance Costs, Noncurrent, Net		20.8	0.0
Debt Issuance Costs, Net		20.8	6.1
Debt, Long-term and Short-term, Combined Amount		3,092.6	5,145.8
Debt Issuance Costs, Current, Net		0.0	(6.1)
Liabilities Subject to Compromise		0.0	(6,397.7)
Debt instrument, face amount		3,534.1
Long-term Debt, Excluding Current Maturities		3,490.0
Long-term Debt [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Liabilities Subject to Compromise		0.0	(3,750.8)
Liabilities Subject to Compromise
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
8.00% debentures due March 2023
Long-term Debt, Excluding Current Maturities [Abstract]
Debt, Long-term and Short-term, Combined Amount		0.0	4.4
Debt instrument, face amount		0.0
Extinguishment of Debt, Amount	$ 4.4
4.75% senior notes due April 2023
Long-term Debt, Excluding Current Maturities [Abstract]
Debt, Long-term and Short-term, Combined Amount		0.0	133.7
Debt instrument, face amount		0.0
Extinguishment of Debt, Amount	133.7
9.50% debentures due May 2022
Long-term Debt, Excluding Current Maturities [Abstract]
Debt, Long-term and Short-term, Combined Amount		0.0	10.4
Debt instrument, face amount		0.0
Extinguishment of Debt, Amount	10.4
5.75% senior notes due August 2022
Long-term Debt, Excluding Current Maturities [Abstract]
Debt, Long-term and Short-term, Combined Amount		0.0	610.3
Debt instrument, face amount		0.0
Five Point Six Two Five Percent Note
Long-term Debt, Excluding Current Maturities [Abstract]
Debt, Long-term and Short-term, Combined Amount		0.0	514.7
Debt instrument, face amount		0.0
Five Point Five Percent Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Debt, Long-term and Short-term, Combined Amount		0.0	387.2
Debt instrument, face amount		0.0
2017 Revolving Credit Facility
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.2
Debt, Long-term and Short-term, Combined Amount			900.0
Secured Debt		0.0	900.0
Debt instrument, face amount		0.0
Term Loan due Sept 2024 [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0.0	1,396.5
Term Loan due 2025 [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0.0	370.7
Debt instrument, face amount		0.0
Ten Point Zero Percent First Lien Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		475.9	495.0
Debt instrument, face amount	495.0	495.0
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		242.2	0.0
Debt instrument, face amount	322.9	321.9
Extinguishment of Debt, Amount	322.9
2017 Replacement Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debt, Long-term and Short-term, Combined Amount		1,374.1
Secured Debt		1,222.1	0.0
Debt instrument, face amount	1,392.9	1,374.1
2018 Replacement Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debt, Long-term and Short-term, Combined Amount		364.8
Secured Debt		326.9	0.0
Debt instrument, face amount	369.7	364.8
Eleven Point Five Percent First Lien Senior Secured Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		20.8	0.0
Secured Debt		650.0	0.0
Debt instrument, face amount		650.0
Ten Point Zero Percent Second Lien Notes due 2029
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt		175.5	0.0
Debt instrument, face amount		328.3
Term Loan and New Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0.0	1,396.5
Debt instrument, face amount		0.0
Ten Point Zero Percent Second Lien Notes (Existing Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0.0	322.9
Debt instrument, face amount	$ 322.9	0.0
Debentures \| 8.00% debentures due March 2023
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debentures \| 4.75% senior notes due April 2023
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debentures \| 9.50% debentures due May 2022
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debentures \| 5.75% senior notes due August 2022
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debentures \| Five Point Six Two Five Percent Note
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Debentures \| Five Point Five Percent Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt \| Term Loan due 2025 [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt \| Ten Point Zero Percent First Lien Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	5.9
Secured Debt \| Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt \| Term Loan and New Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt \| Ten Point Zero Percent Second Lien Notes (Existing Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		$ 0.0	$ 0.0