Refranchisings and Acquisitions (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 25, 2019 USD ($) real_estate restaurant	Dec. 26, 2018 USD ($) real_estate restaurant	Dec. 27, 2017 USD ($) restaurant
Franchisor Disclosure [Line Items]
Noncash consideration	$ 3,000	$ 0	$ 0
Assets held for sale	$ 1,925	$ 723
Number of restaurants \| restaurant	1,703	1,709	1,735
Real Estate
Franchisor Disclosure [Line Items]
Noncash consideration	$ 3,000	$ 0	$ 0
Held-for-sale
Franchisor Disclosure [Line Items]
Assets held for sale, property	1,600	$ 700
Other assets held for sale	200
Assets held for sale, goodwill	$ 100
Number of restaurants \| restaurant	4	3
Number of real estate properties \| real_estate	2	1

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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