CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts	$ 2,524	$ 1,152
Preferred stock, shares authorized	500	500
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	40,207,000	40,225,000
Common stock, shares outstanding	40,207,000	40,225,000