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Related Party - Additional Information (Detail) - USD ($) $ in Thousands			1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 15, 2019	Oct. 18, 2015	Dec. 31, 2020	Jun. 27, 2020	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Related Party Transaction [Line Items]
Initial agreement term		5 years
Fully vested option to purchase shares of common stock					0	0
Dividend yield					0.00%
Ms. Winfrey
Related Party Transaction [Line Items]
Fully vested option to purchase shares of common stock	3,276,000				3,874,000
Compensation expense				$ 32,686
Dividend yield				0.00%
Volatility rate				63.68%
Risk-free interest rate				0.41%
Accounts payable to related parties					$ 76	$ 72
Number of shares purchased from related party			2,782,000
Stock options exercised			1,118,000		1,162,000
Ms. Winfrey \| Selling, General and Administrative Expenses
Related Party Transaction [Line Items]
Compensation expense				$ 32,686
Ms. Winfrey and her related entities
Related Party Transaction [Line Items]
Related Party Transaction, service provided by related party					$ 2,228	2,791	$ 2,208
Related Party, advertising expenses						$ 330
Related Party Transaction, actual costs reimbursed					$ 1,653