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401(k) Plan (Details) - USD ($)
$ in Millions
12 Months Ended
Apr. 01, 2018
Dec. 27, 2019
Dec. 28, 2018
Dec. 29, 2017
Compensation And Retirement Disclosure [Abstract]        
Percentage of pre-tax annual compensation contributed to the plan   15.00%    
Percentage of matching contributions of employee 40.00%     25.00%
Percentage of matching contributions of employee's gross salary 6.00%     6.00%
Company's matching contributions   $ 0.8 $ 1.1 $ 0.5