Fair Value Measurements - Carrying Value and Estimated Fair Values of Outstanding Debt (Detail) - USD ($) $ in Millions	Jun. 29, 2019	Dec. 29, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes, carrying value	$ 1,246.2	$ 1,246.1
Estimate of Fair Value, Fair Value Disclosure
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Outstanding debt, fair value	1,281.6	1,217.5
5.500% senior notes due in 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes, carrying value	$ 504.9	505.9
Interest rate on notes	5.50%
5.500% senior notes due in 2024 \| Estimate of Fair Value, Fair Value Disclosure
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Outstanding debt, fair value	$ 526.4	521.7
5.500% senior notes due in 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes, carrying value	$ 741.3	740.2
Interest rate on notes	5.50%
5.500% senior notes due in 2025 \| Estimate of Fair Value, Fair Value Disclosure
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Outstanding debt, fair value	$ 755.2	$ 695.8

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
-Topic 825
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-Section 50
-Paragraph 10
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Contractual interest rate for funds borrowed, under the debt agreement.

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-Name Accounting Standards Codification
-Topic 210
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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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