Select Balance Sheet and Statement of Operations Information - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Select Balance Sheet And Statement Of Operations Information [Abstract]
Cost of goods sold	$ 6,149	$ 5,829	$ 13,352	$ 17,142
Provision for inventory obsolescence	1,433		1,433		$ 1,439
Depreciation expense	$ 318	$ 195	$ 1,095	$ 663