Net Loss Per Share Attributable to Common Stockholders - Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance	$ 976,723	$ 1,045,034	$ 1,013,953	$ 1,061,865
Foreign currency translation adjustment	17	23	(170)	(42)
Unrealized loss on available-for-sale securities	(3,063)	(147)	(9,745)	(225)
Ending balance	993,738	1,029,090	993,738	1,029,090
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance	(9,496)	(137)	(2,627)	6
Ending balance	(12,542)	(261)	(12,542)	(261)
Unrealized Loss on Available-for-Sale Securities
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance	(8,924)	27	(2,242)	105
Foreign currency translation adjustment	0	0	0	0
Unrealized loss on available-for-sale securities	(3,063)	(147)	(9,745)	(225)
Ending balance	(11,987)	(120)	(11,987)	(120)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance	(572)	(164)	(385)	(99)
Foreign currency translation adjustment	17	23	(170)	(42)
Unrealized loss on available-for-sale securities	0	0	0	0
Ending balance	$ (555)	$ (141)	$ (555)	$ (141)