Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 26, 2019	Dec. 31, 2018
Carrying amount and estimated fair value of long term debt
Carrying Amount	$ 2,038.5	$ 1,792.1
Fair Value	2,115.0	1,725.7
Secured Debt Term A [Member]
Debt Instrument [Line Items]
Secured Debt, Current	22.7	22.7
Secured Long-term Debt, Noncurrent	427.1	182.0
Carrying amount and estimated fair value of long term debt
Carrying Amount	449.8	204.7
Fair Value	450.7	197.8
Senior unsecured notes due 2022 [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	299.0	292.9
Senior Notes, Noncurrent	298.9	298.5
Senior Unsecured Notes Due 2023 [Domain]
Carrying amount and estimated fair value of long term debt
Fair Value	309.0	297.5
Senior Notes, Noncurrent	298.2	297.9
Senior Unsecured Notes Due 2026 [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	306.0	274.5
Senior Notes, Noncurrent	297.7	297.5
SeniorUnsecuredNotesDue 2028 [Member] [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	750.3	663.0
Senior Notes, Noncurrent	$ 693.9	$ 693.5

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 10
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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