Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Mar. 31, 2020	Dec. 31, 2019
Common stock, shares outstanding	24,318	23,554
Class A common stock
Common stock, par value	$ 0.001	$ 0.001
Common stock authorized	125,000	125,000
Common Stock, Shares, Issued	24,318	23,554
Common stock, shares outstanding	24,318	23,554
Class B common stock
Common stock, par value	$ 0.001	$ 0.001
Common stock authorized	100,000	100,000
Common Stock, Shares, Issued	4,049	4,752
Common stock, shares outstanding	4,049	4,752