Refranchisings and Acquisitions - Acquisitions (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 25, 2019 USD ($) parcel restaurant	Sep. 26, 2018 USD ($) parcel restaurant	Sep. 25, 2019 USD ($) parcel restaurant	Sep. 26, 2018 USD ($) parcel restaurant
Business Acquisition [Line Items]
Restaurants acquired from franchisees \| restaurant	0	0	0	6
Purchase price allocation of reacquired franchise rights	$ 0	$ 0	$ 0	$ 5,434
Purchase price allocation of property	0	0	0	1,121
Purchase price allocation of goodwill	0	0	0	1,574
Total purchase price to reacquire franchised restaurants	0	0	0	8,129
Financing leases recorded	0	0	0	2,409
Real Estate [Member]
Business Acquisition [Line Items]
Total purchase price to reacquire franchised restaurants	$ 4,750	$ 0	$ 9,456	$ 1,787
Real estate parcels acquired \| parcel	2	0	4	1

Amount of financing lease obligations assumed during the period.

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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 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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