Contract Liabilities: Activity (Details) - USD ($)	6 Months Ended
	Jun. 26, 2021	Jun. 27, 2020
Activity of the current and noncurrent deferred franchise revenue
Balance at beginning of period	$ 8,708,300	$ 9,575,500
Franchise and software license fees collected from franchisees, excluding amount earned as revenue during the period	755,400	473,500
Fees earned that were included in the balance at the beginning of the period	(875,700)	(885,600)
Balance at end of period	$ 8,588,000	$ 9,163,400