Revenue - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
	Aug. 31, 2016	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2014
Revenues [Line Items]
Long-term trade receivables		$ 300,000		$ 200,000
Long-term trade credit maintenance services term		1 year
Allowance for doubtful accounts		$ 0		$ 0
Deferred revenue, recognized		3,300,000	$ 7,900,000
Company recognized revenue from performance obligations satisfied in a prior period		$ 0	$ 900,000
Minimum
Revenues [Line Items]
Expected long-term trade receivables collection period		2 years
Maximum
Revenues [Line Items]
Expected long-term trade receivables collection period		3 years
Itochu Corporation Agreement | Distribution Rights
Revenues [Line Items]
Distribution revenue reclassified as deferred revenue					$ 4,000,000
Remaining term of distribution agreement	8 years 6 months