Income Taxes: Other (Details) - USD ($)	12 Months Ended
	Dec. 25, 2021	Dec. 26, 2020
Deferred tax assets, valuation allowance
Valuation allowance	$ 908,200	$ 2,822,600
Unrecognized Tax Benefits
Unrecognized tax benefits, including interest and penalties	821,700	621,100
Interest and penalties accrued related to unrecognized tax benefit	144,500	111,000
Activity related to the company's unrecognized tax benefits
Balance at the beginning of the period	510,100	499,000
Increases related to current year tax positions	190,000	144,500
Subtractions for tax positions of prior years	(22,900)
Expiration of the statute of limitations for the assessment of taxes		(133,400)
Balance at the end of the period	$ 677,200	$ 510,100
Period over which various statutes of limitations are expected to expire	12 months