Acquisitions (Details)	3 Months Ended	6 Months Ended
Jun. 26, 2019 USD ($)	Jun. 27, 2018 USD ($)	Jun. 26, 2019 USD ($)	Jun. 27, 2018 USD ($)
Business Acquisition [Line Items]
Restaurants acquired from franchisees	0	1	0	6
Purchase price allocation of reacquired franchise rights	$ 0	$ 119,000	$ 0	$ 5,434,000
Purchase price allocation of property	0	92,000	0	1,121,000
Purchase price allocation of goodwill	0	0	0	1,574,000
Total purchase price to reacquire franchised restaurants	0	211,000	0	8,129,000
Financing leases recorded	$ 0	$ 0	$ 0	$ 2,409,000
Real Estate [Member]
Business Acquisition [Line Items]
Real estate parcels acquired	0	1	2	1
Purchase price allocation of property	$ 0	$ 1,787,000	$ 4,706,000	$ 1,787,000

Amount of financing lease obligations assumed during the period.

No definition available.

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Number of pieces of real estate acquired.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The number of franchises purchased during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period.

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