Schedule of Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 30, 2020		Sep. 30, 2020		Jun. 30, 2020		Mar. 31, 2020		Dec. 31, 2019		Sep. 30, 2019		Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 56,560		$ 51,406		$ 50,414		$ 52,102		$ 46,936		$ 51,101		$ 45,904		$ 23,038		$ 210,482	$ 166,979	$ 43,130
Gross profit	16,642		3,330		(5,824)		10,507		(57,007)		15,853		12,273		5,385		24,655	(23,496)	14,275
Operating loss	(21,282)		(32,772)		(75,820)		(71,250)		(216,624)		(23,785)		(32,961)		(28,332)
Net loss	$ (2,947)		$ (2,316)		$ (81,687)		$ (184,123)		$ (219,148)		$ (36,351)		$ (36,301)		$ (29,369)		$ (271,073)	$ (321,169)	$ (67,723)
Net loss per share - basic and diluted	$ (0.02)	[1]	$ (0.02)	[1]	$ (0.65)	[1]	$ (1.73)	[1]	$ (2.14)	[1]	$ (0.37)	[1]	$ (0.37)	[1]	$ (0.31)	[1]	$ (2.15)	$ (3.20)	$ (0.82)

[1] Earnings per share for the four quarters combined may not equal earnings per share for the year due to rounding.