Segment Reporting: (Details)	12 Months Ended
	Dec. 25, 2021 USD ($) item	Dec. 26, 2020 USD ($)	Dec. 28, 2019 USD ($)
Segment Reporting
Number of reportable business segments | item	2
Total revenue	$ 78,216,200	$ 66,061,800	$ 73,298,900
Total operating income	51,336,200	40,211,500	43,131,100
Total depreciation and amortization	430,600	484,700	400,100
Total identifiable assets	26,899,000	31,343,200
Franchising | Canadian operations
Segment Reporting
Total revenue	4,900,000	4,000,000.0	4,700,000
Operating | Franchising
Segment Reporting
Total revenue	67,067,900	51,577,800	57,243,100
Total operating income	44,832,100	31,880,200	35,169,900
Total depreciation and amortization	243,900	285,300	281,600
Total identifiable assets	4,907,800	4,848,300
Operating | Leasing
Segment Reporting
Total revenue	11,148,300	14,484,000	16,055,800
Total operating income	6,504,100	8,331,300	7,961,200
Total depreciation and amortization	186,700	199,400	$ 118,500
Total identifiable assets	3,600,500	14,462,600
Unallocated
Segment Reporting
Total identifiable assets	$ 18,390,700	$ 12,032,300