Condensed Consolidated Statements of Comprehensive (Loss) Income - 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 loss	$ (48,452)	$ (25,985)	$ (121,109)	$ (73,639)
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale securities, net of tax	73	(7)	(61)	93
Foreign currency translation adjustments	457	(760)	835	(922)
Other comprehensive income (loss)	530	(767)	774	(829)
Total comprehensive loss	$ (47,922)	$ (26,752)	$ (120,335)	$ (74,468)