Annual report pursuant to Section 13 and 15(d)

Stock Incentive Plans Stock Incentive Plans - Summary of Weighted Average Assumptions (Details)

v3.20.4
Stock Incentive Plans Stock Incentive Plans - Summary of Weighted Average Assumptions (Details) - Stock Options - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 27, 2020
Dec. 29, 2019
Dec. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate (as a percent) 0.50% 0.00% 2.50%
Expected years until exercise 4 years 8 months 12 days 0 years 3 years 2 months 12 days
Expected stock volatility (as a percent) 61.00% 0.00% 43.40%
Dividend yield (as a percent) 0.00% 0.00% 0.00%
Weighted average Black-Scholes fair value per share at date of grant (in dollars per share) $ 6.28 $ 0 $ 16.56
Total intrinsic value of options exercised $ 30 $ 20 $ 390