Stock-Based Compensation (Performance-Contingent Restricted Stock) - Additional Information (Detail) - Performance Contingent Restricted Stock $ in Millions	3 Months Ended	6 Months Ended
Jul. 13, 2019 USD ($)	Jul. 13, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested restricted stock granted by the Omnibus Plan	$ 11.2	$ 11.2
Expected weighted-average period to recognize compensation cost (years)		2 years 7 months 17 days
Intrinsic value of shares vested	$ 18.6	$ 18.6

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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