Investment in Leasing Operations: Credit Losses (Details) - USD ($)	12 Months Ended
	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Activity in the allowance for credit losses for leasing operations
Balance at beginning of period	$ 270,200	$ 580,600	$ 861,200
Provisions for credit losses	(206,600)	(79,300)	(78,300)
Recoveries		(11,800)	21,900
Deductions for amounts written-off		(219,300)	(224,200)
Balance at end of period	63,600	270,200	$ 580,600
Investment In Leases
Total investment in direct financing and sales-type leases	3,163,000	13,512,300
Allowance for Credit Losses
Total	63,600	270,200
Investment in leases
Investment In Leases
Collectively evaluated for loss potential	3,163,000	13,512,300
Total investment in direct financing and sales-type leases	3,163,000	13,512,300
Allowance for Credit Losses
Collectively evaluated for loss potential	63,600	270,200
Total	$ 63,600	$ 270,200