Financial Instruments and Fair Value Measurements (Narrative) (Details) $ in Millions		3 Months Ended		6 Months Ended
	Nov. 14, 2028	Jun. 28, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 28, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 29, 2023 USD ($)	Nov. 14, 2023 USD ($)	Mar. 13, 2023 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Notional Amount								$ 860.0
Derivative, Interest Rate Cap, Premium		$ 20.0
Derivative, Cap Interest Rate								3.84%
Equity Securities, FV-NI, Unrealized Gain (Loss)		(4.3)	$ 1.2	$ 2.7	$ 16.3
Interest Rate Cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Unrealized Gain (Loss) on Derivatives		0.8		1.3
Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Unrealized Gain (Loss) on Derivatives		0.6		5.3
Professional Fees Escrow Account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Restricted Cash, Fair Value Disclosure		$ 0.0		$ 0.0			$ 24.0
Takeback Term Loans | Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Discount Rate, Present Value of Future Cash Flows		2.03%		2.03%
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 1 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity		4 years 4 months 24 days		4 years 4 months 24 days
Derivative, Contract End Date	Nov. 14, 2028
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 1 | Derivative Financial Instruments, Liabilities | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.700		0.700
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 1 | Derivative Financial Instruments, Liabilities | Measurement Input Coupon Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.1475		0.1475
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 2 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity		4 years 4 months 24 days		4 years 4 months 24 days
Derivative, Contract End Date	Nov. 14, 2028
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 2 | Derivative Financial Instruments, Liabilities | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.100		0.100
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 2 | Derivative Financial Instruments, Liabilities | Measurement Input Coupon Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.1475		0.1475
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 3 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity		4 years 4 months 24 days		4 years 4 months 24 days
Derivative, Contract End Date	Nov. 14, 2028
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 3 | Derivative Financial Instruments, Liabilities | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.070		0.070
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Scenario 3 | Derivative Financial Instruments, Liabilities | Measurement Input Coupon Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.1475		0.1475
Fourteen Point Seven Five Percent Second-Out Takeback Notes | Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Discount Rate, Present Value of Future Cash Flows		3.03%		3.03%
Seven Point Five Zero Percent to Nine Point Five Zero Percent Plus SOFR First-Out Takeback Notes | Scenario 1 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity		4 years 4 months 24 days		4 years 4 months 24 days
Derivative, Contract End Date	Nov. 14, 2028
Seven Point Five Zero Percent to Nine Point Five Zero Percent Plus SOFR First-Out Takeback Notes | Scenario 1 | Derivative Financial Instruments, Liabilities | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.700		0.700
Seven Point Five Zero Percent to Nine Point Five Zero Percent Plus SOFR First-Out Takeback Notes | Scenario 2 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity		4 years 4 months 24 days		4 years 4 months 24 days
Derivative, Contract End Date	Nov. 14, 2028
Seven Point Five Zero Percent to Nine Point Five Zero Percent Plus SOFR First-Out Takeback Notes | Scenario 2 | Derivative Financial Instruments, Liabilities | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.100		0.100
Seven Point Five Zero Percent to Nine Point Five Zero Percent Plus SOFR First-Out Takeback Notes | Scenario 3 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity		4 years 4 months 24 days		4 years 4 months 24 days
Derivative, Contract End Date	Nov. 14, 2028
Seven Point Five Zero Percent to Nine Point Five Zero Percent Plus SOFR First-Out Takeback Notes | Scenario 3 | Derivative Financial Instruments, Liabilities | Measurement Input Probability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability, Measurement Input | pURE		0.070		0.070
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability		$ 20.4		$ 20.4		$ 15.1
Level 3 | Other current and non-current assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash surrender value of life insurance		44.5		44.5		45.3
Level 3 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability		20.4		20.4		15.1
Level 2 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability		0.0		0.0		0.0
Level 1 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability		0.0		0.0		0.0
Indemnification Agreement | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Restricted Cash and Cash Equivalents		$ 64.9		$ 64.9		$ 80.7