Refranchisings and Acquisitions (Acquisition Activity) (Details) $ in Thousands	12 Months Ended
Dec. 25, 2019 USD ($) parcel restaurant	Dec. 26, 2018 USD ($) parcel restaurant	Dec. 27, 2017 USD ($) parcel restaurant
Business Acquisition [Line Items]
Restaurants acquired from franchisees \| restaurant	0	6	11
Purchase price allocation:
Reacquired franchise rights	$ 0	$ 5,434	$ 4,476
Property	0	1,121	1,293
Goodwill	0	1,574	3,022
Total purchase price	0	8,129	8,791
Finance leases recorded	0	2,409	2,321
Real Estate
Purchase price allocation:
Total purchase price	$ 11,320	$ 1,787	$ 4,062
Real estate parcels acquired \| parcel	5	1	2
Former Franchise
Business Acquisition [Line Items]
Restaurants acquired from franchisees \| restaurant			1

Amount of financing lease obligations assumed during the period.

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Purchase Price Allocation [Abstract]

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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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