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Related Party - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
	Dec. 15, 2019	Oct. 18, 2015	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019	Dec. 28, 2019
Related Party Transaction [Line Items]
Initial agreement term		5 years
Ms. Winfrey
Related Party Transaction [Line Items]
Fully vested option to purchase shares of common stock	3,276
Dividend yield					0.00%
Volatility rate					63.68%
Risk-fee interest rate					0.41%
Accounts payable to related parties			$ 268		$ 268		$ 72
Number of shares purchased from related party					604,000
Stock options exercised					297,000
Ms. Winfrey and her related entities
Related Party Transaction [Line Items]
Related Party Transaction, service provided by related party			823	$ 720	$ 1,761	$ 2,003
Related Party Transaction, actual costs reimbursed			141		$ 1,650
Selling, General and Administrative Expenses \| Ms. Winfrey
Related Party Transaction [Line Items]
Compensation expense			$ 32,686