CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 3,618	$ 3,470	$ (9,356)	$ (19,166)
Other comprehensive income (loss):
Unrealized gain (loss) on investments	(68)	(9)	57	29
Comprehensive income (loss)	$ 3,550	$ 3,461	$ (9,299)	$ (19,137)