Financial Instruments and Fair Value Measurements (Schedule of Carrying Amount and Fair Value of Long-term Debt) (Details) - USD ($) $ in Millions	Sep. 29, 2023	Dec. 30, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	$ 2,703.0	$ 2,684.6
Long-term Debt	0.0	3,048.5
Total Debt	3,892.0	3,092.6
Secured Debt	3,892.0
10.00% Second Lien Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	24.2	216.8
Long-term Debt		242.2
Total Debt		242.2
Secured Debt	321.9
10.00% First Lien Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	393.0	425.9
Long-term Debt		475.9
Total Debt		475.9
Secured Debt	495.0
Eleven Point Five Percent First Lien Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	574.1	552.6
Long-term Debt		650.0
Total Debt		650.0
Secured Debt	650.0
Ten Point Zero Percent Second Lien Notes due 2029
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	28.7	176.7
Long-term Debt		175.5
Total Debt		175.5
Secured Debt	328.3
2017 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	1,025.2	1,037.8
Total Debt		1,222.1
Secured Debt	1,356.7
2018 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	272.2	274.8
Total Debt		326.9
Secured Debt	360.1
Debtor-In-Possession Financing
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	285.6	0.0
Total Debt		0.0
Secured Debt	280.0	0.0
Receivables Financing Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	100.0	0.0
Secured Debt	$ 100.0	$ 0.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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