Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
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- Definition

Amount of contingent rental revenue recognized for the period under lease, based on the occurrences of an event or condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

No definition available.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Leases - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2018	Sep. 26, 2018	Jun. 27, 2018	Mar. 28, 2018	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 26, 2018	Dec. 27, 2017	Dec. 28, 2016
Property Subject to or Available for Operating Lease [Line Items]
Initial term of lease	20 years								20 years
Sublease income, contingent rental income									$ 700	$ 800	$ 1,000
Company-operated restaurant revenue	$ 106,261	$ 112,178	$ 111,633	$ 105,756	$ 95,202	$ 101,155	$ 105,573	$ 99,771	$ 435,828	401,701	380,123
Minimum
Property Subject to or Available for Operating Lease [Line Items]
Lessor, term of contract	3 years								3 years
Maximum
Property Subject to or Available for Operating Lease [Line Items]
Lessor, term of contract	20 years								20 years
Franchise, Rental Income
Property Subject to or Available for Operating Lease [Line Items]
Company-operated restaurant revenue									$ 500	$ 500	$ 500