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Related Party - Additional Information (Detail) - USD ($) $ in Thousands			12 Months Ended
	Dec. 15, 2019	Oct. 18, 2015	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Related Party Transaction [Line Items]
Initial agreement term		5 years
Option awards granted during period			0	0
Stock options exercised			74,000
Ms. Winfrey
Related Party Transaction [Line Items]
Option awards granted during period	3,276
Purchased good from related entity					$ 84
Accounts payable to related parties			$ 72	$ 62
Number of shares purchased from related party			954,000
Stock options exercised			1,405,000
Ms. Winfrey and her related entities
Related Party Transaction [Line Items]
Related Party Transaction, service provided by related party			$ 2,791	$ 2,208	$ 4,266
Related Party, advertising expenses			$ 330