Financial Instruments and Fair Value Measurements (Schedule of Carrying Amount and Fair Value of Long-term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 30, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term Debt, Current Maturities	$ 44.1	$ 44.1
Total debt, fair value	2,634.2	2,684.6
Long-term Debt	3,061.5	3,048.5
Total Debt	3,105.6	3,092.6
10.00% Second Lien Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	222.1	216.8
Long-term Debt	249.8	242.2
10.00% First Lien Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	415.6	425.9
Long-term Debt	478.0	475.9
Eleven Point Five Percent First Lien Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	536.6	552.6
Long-term Debt	650.0	650.0
Ten Point Zero Percent Second Lien Notes due 2029
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total debt, fair value	192.0	176.7
Long-term Debt	179.8	175.5
2017 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term Debt, Current Maturities	34.8	34.8
Total debt, fair value	1,005.3	1,037.8
Long-term Debt	1,186.6	1,187.3
Total Debt	1,221.4	1,222.1
2018 Replacement Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term Debt, Current Maturities	9.3	9.3
Total debt, fair value	262.6	274.8
Long-term Debt	317.3	317.6
Total Debt	$ 326.6	$ 326.9

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-4

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

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.

+ References

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