Investment in Leasing Operations: Leasing Income (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 24, 2022	Sep. 25, 2021	Sep. 24, 2022	Sep. 25, 2021
Leasing income
Interest income on direct financing and sales-type leases	$ 153,500	$ 362,200	$ 637,300	$ 1,464,700
Selling profit (loss) at commencement of sales-type leases		164,300	1,298,000	1,594,300
Operating lease income	651,900	436,700	1,562,000	1,397,500
Income on sales of equipment under lease	865,900	988,500	1,798,000	3,214,000
Other	90,800	314,500	550,500	681,300
Leasing income	$ 1,762,100	$ 2,266,200	$ 5,845,800	$ 8,351,800