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Revenue Recognition - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 01, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Contract assets, current	$ 13,747		$ 13,747			$ 9,448
Contract assets, long term	8,575		8,575			11,807
Impairment loss of contract assets	2,000	$ 4,000	3,168	$ 4,622
ASC 606
Disaggregation Of Revenue [Line Items]
Deferred revenue	3,800		3,800
ASC 606 \| Other Assets - Current
Disaggregation Of Revenue [Line Items]
Contract assets, current	13,700		13,700			9,400
ASC 606 \| Other Assets Noncurrent
Disaggregation Of Revenue [Line Items]
Contract assets, long term	8,600		$ 8,600			$ 11,800
Starter China Limited
Disaggregation Of Revenue [Line Items]
Impairment loss of contract assets	$ 1,500
Subsequent Event
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation					$ 380,700