Balance Sheet Information - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Inventory receipts	$ 2,524	$ 1,431
Payroll and other employee benefits	1,169	1,605
Paid time off	1,146	855
Employee stock purchase plan	419	228
Professional fees and contractors	416	246
Deferred revenues	255	241
Warranties	250	444
Operating leases	177	282
Income and sales taxes	182	133
Real estate taxes	116	152
Customer refunds for estimated returns	109	147
Finance leases	71	77
Restructuring	4	45
Short-term incentive plan	0	2,553
Leasehold improvements	0	702
Other	256	241
Total	$ 7,094	$ 9,382