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Debt (Schedule of Long term debt) (Details) - USD ($) $ in Millions	Nov. 14, 2023	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022
Long-term Debt, Current Maturities [Abstract]
Long-term Debt, Current Maturities		$ (6.5)	$ (44.1)
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross		1,758.8	3,048.5
Debt Issuance Costs, Noncurrent, Net		2.9	20.8
Debt Issuance Costs, Net		2.9	20.8
Debt, Long-term and Short-term, Combined Amount		1,765.3	3,092.6
Debt Issuance Costs, Current, Net		0.0	0.0
Debt instrument, face amount		1,647.8	3,534.1
Long-term Debt, Excluding Current Maturities		1,641.3	3,490.0
Ten Point Zero Percent First Lien Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0.0	475.9
Debt instrument, face amount		0.0	495.0	$ 495.0
Ten Point Zero Percent Second Lien Notes (New 2L Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Secured Debt		0.0	242.2
Debt instrument, face amount		0.0	321.9
Extinguishment of Debt, Amount	$ 321.9
2017 Replacement Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt		0.0	1,222.1
Debt instrument, face amount		0.0	1,374.1	1,392.9
2018 Replacement Term Loan
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt		0.0	326.9
Debt instrument, face amount		0.0	364.8	369.7
Eleven Point Five Percent First Lien Senior Secured Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	20.8
Secured Debt		0.0	650.0
Debt instrument, face amount		0.0	650.0
Extinguishment of Debt, 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		0.0	175.5
Debt instrument, face amount		0.0	328.3
Extinguishment of Debt, Amount	328.3
Ten Point Zero Percent Second Lien Notes (Existing Notes)
Long-term Debt, Excluding Current Maturities [Abstract]
Debt instrument, face amount				322.9
First-Out Takeback Term Loan Due November 2028
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt		243.4	0.0
Debt instrument, face amount	229.4	228.8	0.0
Second-Out Takeback Term Loan Due November 2028
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt		685.5	0.0
Debt instrument, face amount	642.0	640.4	0.0
Fourteen Point Seven Five Percent Second-Out Takeback Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
Secured Debt		836.4	0.0
Debt instrument, face amount	778.6	778.6	0.0
Receivables Financing Facility
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		2.9	0.0
Secured Debt		0.0	0.0
Debt instrument, face amount		0.0	0.0	200.0
Ten Point Zero Percent First Lien Notes Due April 2025
Long-term Debt, Excluding Current Maturities [Abstract]
Debt instrument, face amount				$ 495.0
Extinguishment of Debt, Amount	$ 495.0
Secured Debt \| Ten Point Zero Percent First Lien Notes [Member]
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net		0.0	0.0
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