Segment Reporting: (Details)	3 Months Ended
	Apr. 01, 2017 USD ($) item	Mar. 26, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting
Number of reportable business segments | item	2
Total revenue	$ 17,623,800	$ 16,180,300
Total operating income	9,135,400	8,038,600
Total depreciation and amortization	98,500	109,200
Total identifiable assets	47,396,000		$ 48,581,600
Operating | Franchising
Segment Reporting
Total revenue	11,764,200	11,667,600
Total operating income	6,142,500	5,909,700
Total depreciation and amortization	75,800	84,800
Total identifiable assets	3,208,400		3,141,300
Operating | Leasing
Segment Reporting
Total revenue	5,859,600	4,512,700
Total operating income	2,992,900	2,128,900
Total depreciation and amortization	22,700	$ 24,400
Total identifiable assets	43,234,600		42,735,600
Unallocated
Segment Reporting
Total identifiable assets	$ 953,000		$ 2,704,700