CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts receivable, allowance for credit losses	$ 7,323	$ 7,253
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.000001	$ 0.000001
Preferred stock, authorized shares	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock
Common stock, par value (in dollars per share)	$ 0.000001	$ 0.000001
Class A common stock
Common stock
Common stock, authorized shares	1,000,000,000	1,000,000,000
Common stock, shares issued	43,025,000	42,338,000
Common stock, shares outstanding	43,025,000	42,338,000
Class B common stock
Common stock
Common stock, authorized shares	95,000,000	95,000,000
Common stock, shares issued	4,506,000	5,002,000
Common stock, shares outstanding	4,506,000	5,002,000