Fair Value Measurements (Details) - USD ($) $ in Millions	Oct. 01, 2020	Dec. 31, 2019	Sep. 26, 2019
Carrying amount and estimated fair value of long term debt
Carrying Amount	$ 2,774.2	$ 2,827.8
Fair Value	2,609.7	2,885.7
Long-term Line of Credit, Noncurrent	0.0	800.0
Lines of Credit, Fair Value Disclosure		800.0	$ 0.0
Senior Secured Notes Due 2025 [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	1,204.2	0.0
Senior Notes	1,183.4
Senior Notes, Noncurrent	1,183.4	0.0
Senior Notes, Current	0.0	0.0
Secured Debt Term A [Member]
Debt Instrument [Line Items]
Secured Debt, Current	0.0	22.8
Secured Long-term Debt, Noncurrent	0.0	415.7
Carrying amount and estimated fair value of long term debt
Carrying Amount	0.0	438.5
Fair Value	0.0	440.1
Senior Unsecured Notes Due 2023 [Domain]
Carrying amount and estimated fair value of long term debt
Fair Value	267.0	307.2
Senior Notes	298.7
Senior Notes, Noncurrent	298.7	298.3
Senior Notes, Current	0.0	0.0
Senior Unsecured Notes Due 2026 [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	279.9	305.6
Senior Notes	298.0
Senior Notes, Noncurrent	298.0	297.8
Senior Notes, Current	0.0	0.0
SeniorUnsecuredNotesDue2028 [Member] [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	575.3	734.4
Senior Notes, Noncurrent	694.5	694.1
SeniorUnsecuredFloatingRateNotes [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	283.3	298.4
Senior Notes	299.6
Senior Notes, Noncurrent	0.0	299.1
Senior Notes, Current	$ 299.6	$ 0.0

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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