Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 26, 2025	Dec. 27, 2024	Nov. 14, 2023
Current maturities of long-term debt:
Principal	$ 37.5	$ 3.9
Carrying Value	37.5	3.9
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Long-term debt:
Principal	3,647.5	861.7
Carrying Value	3,716.7	911.7
Unamortized Discount and Debt Issuance Costs	27.6	2.2
Total debt, principal	3,685.0	865.6
Total debt, carrying value	3,754.2	915.6
Total debt, unamortized discount and debt issuance costs	27.6	2.2
Term Loan due July 2030
Current maturities of long-term debt:
Principal	22.5	0.0
Carrying Value	22.5	0.0
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Long-term debt:
Principal	1,177.5	0.0
Carrying Value	1,177.5	0.0
Unamortized Discount and Debt Issuance Costs	26.1	0.0
Term Loan due April 2031
Current maturities of long-term debt:
Principal	15.0	0.0
Carrying Value	15.0	0.0
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Long-term debt:
Principal	1,470.0	0.0
Carrying Value	1,476.4	0.0
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Second-Out Takeback Term Loan Due November 2028
Current maturities of long-term debt:
Principal	0.0	3.9
Carrying Value	0.0	3.9
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Long-term debt:
Principal	0.0	384.5
Carrying Value	0.0	406.3
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Total debt, principal			$ 642.0
8.50% Senior Secured Notes due April 2031
Long-term debt:
Principal	1,000.0	0.0
Carrying Value	1,062.8	0.0
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Revolving Credit Facility due July 2030
Long-term debt:
Principal	0.0	0.0
Carrying Value	0.0	0.0
Unamortized Discount and Debt Issuance Costs	1.5	0.0
14.75% Second-Out Takeback Notes
Long-term debt:
Principal	0.0	477.2
Carrying Value	0.0	505.4
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Total debt, principal			$ 778.6
Receivables Financing Facility
Long-term debt:
Principal	0.0	0.0
Carrying Value	0.0	0.0
Unamortized Discount and Debt Issuance Costs	$ 0.0	$ 2.2

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