Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Allowance for doubtful accounts receivable	$ 826	$ 615
Provision for sales returns	$ 1,212	$ 1,400
Class 1 common stock [Member]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	233,333,333	250,000,000
Common stock, shares issued	0	16,666,667
Common stock, shares outstanding	0	16,666,667
Class 2 common stock [Member]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	133,289,944	86,114,560
Common stock, shares outstanding	133,289,944	86,114,560