Financial Instruments and Fair Value Measurements (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 29, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 29, 2023 USD ($)	Nov. 21, 2023	Nov. 14, 2023 USD ($)	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 Liability, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities
Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ 7.0	$ 15.1
Interest Rate Cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Unrealized Gain (Loss) on Derivatives	2.1
Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Unrealized Gain (Loss) on Derivatives	5.9
Professional Fees Escrow Account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Restricted Cash, Fair Value Disclosure	13.8				$ 24.0
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Cap Interest Rate						3.84%
Takeback Term Loans | Scenario 1 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity					4 years 7 months 6 days
Takeback Term Loans | 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				0.3500
Takeback Term Loans | Scenario 2 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity					4 years 7 months 6 days
Takeback Term Loans | 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				0.3500
Takeback Term Loans | Scenario 3 | Derivative Financial Instruments, Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative, Remaining Maturity					4 years 7 months 6 days
Takeback Term Loans | 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				0.1225
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 7 months 6 days
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				0.3500
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
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 7 months 6 days
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				0.3500
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
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 7 months 6 days
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				0.1225
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
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability	21.0		$ 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	44.8		45.3
Level 3 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability	21.0		15.1
Level 2 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability	0.0		0.0
Level 1 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative Liability	0.0		0.0
Indemnification Agreement | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Restricted Cash and Cash Equivalents	$ 77.9		$ 80.7