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Equity Compensation - Vesting (Details) - $ / shares	12 Months Ended
Equity Compensation - Vesting (Details) - $ / shares	Dec. 27, 2020	Dec. 29, 2019	Dec. 30, 2018
Equity Compensation
Award vesting period, in years	3 years
Weighted average grant-date fair values of options granted		$ 11.69	$ 15.27
Options granted, shares	0	353,000	456,000
Options
Equity Compensation
Award vesting period, in years	3 years
Options \| Maximum
Equity Compensation
Award expiration period, in years	10 years