Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (3,468)	$ (4,857)	$ (13,938)	$ (16,592)
Other comprehensive loss, net:
Change in unrealized gain on investments, net of tax	1,806	294	850	719
Comprehensive loss	$ (1,662)	$ (4,563)	$ (13,088)	$ (15,873)