Shareholders' Equity (Deficit): Additional Information (Details) - Stock options - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Additional disclosures
Total intrinsic value of options exercised	$ 22,700,000	$ 8,300,000	$ 7,700,000
Total fair value of shares vested	$ 8,600,000	$ 7,800,000	$ 7,300,000
Shares of previously owned common stock surrendered as payment for option shares exercised	0	2,249	2,927
Compensation expense	$ 1,666,400	$ 1,976,100	$ 1,956,600
Total unrecognized compensation expense	$ 3,700,000
Weighted average period for recognition of unrecognized compensation expense	2 years 7 months 6 days