Operating Property - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Property, Plant and Equipment [Line Items]
Finance leased assets gross	$ 199,045,000	$ 222,993,000
Finance leases balance sheet assets by major class net.	139,259,000	156,439,000
Finance leases	$ 31,633,000	$ 29,054,000	$ 46,595,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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