Investment in Leasing Operations: Summary of Leasing Operations (Details) - USD ($)	Sep. 25, 2021	Dec. 26, 2020
Direct financing and sales-type leases:
Minimum lease payments receivable	$ 5,111,300	$ 12,536,300
Estimated unguaranteed residual value of equipment	1,643,300	2,950,100
Unearned lease income net of initial direct costs deferred	(611,100)	(1,439,500)
Security deposits	(1,494,500)	(2,169,000)
Equipment installed on leases not yet commenced	431,800	1,634,400
Total investment in direct financing and sales-type leases	5,080,800	13,512,300
Allowance for credit losses	(102,900)	(270,200)
Net investment in direct financing and sales-type leases	4,977,900	13,242,100
Operating leases:
Operating lease assets	469,800	599,100
Less accumulated depreciation and amortization	(406,100)	(580,100)
Net investment in operating leases	63,700	19,000
Total net investment in leasing operations	5,041,600	13,261,100
Net investment in leases - current	3,884,600	8,687,500
Net investment in leases - long-term	1,157,000	$ 4,573,600
Net investment in leases - long-term	$ 1,100,000