Assets and Liabilities Held for Sale (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) restaurant	Jul. 01, 2018 USD ($)	Jun. 30, 2019 USD ($) restaurant	Jul. 01, 2018 USD ($)
Assets and Liabilities Held for Sale
Number of stores available to be refranchised | restaurant	40		40
Expected time to sell markets			12 months
Loss recognized upon transfer to held for sale			$ 0
Summary of associated assets classified as held for sale:
Cash and cash equivalents	$ 26,000		26,000
Inventories	258,000		258,000
Property and equipment, net	4,980,000		4,980,000
Right-of-use assets	4,015,000		4,015,000
Goodwill	1,726,000		1,726,000
Total assets held for sale	11,005,000		11,005,000
Lease liabilities	4,199,000		4,199,000
Total liabilities held for sale	4,199,000		4,199,000
Income before income taxes of restaurants classified as held for sale	$ 612,000	$ 742,000	$ 1,200,000	$ 1,200,000