Receivables (Details) - USD ($) $ in Thousands	Sep. 25, 2019	Dec. 26, 2018
Receivables [Abstract]
Trade accounts receivable from franchisees, gross, current	$ 12,054	$ 11,459
Financing receivables from franchisees, gross, current	4,985	3,211
Allowance for doubtful accounts	(290)	(300)
Total current receivables, net	19,903	26,283
Noncurrent assets (included as a component of other noncurrent assets):
Financing receivables from franchisees and other	450	1,528
Vendor receivables [Member]
Receivables [Abstract]
Other receivables, gross, current	1,386	4,016
Credit card receivables [Member]
Receivables [Abstract]
Other receivables, gross, current	876	5,955
Other [Member]
Receivables [Abstract]
Other receivables, gross, current	$ 892	$ 1,942

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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