Investments - Summary of Cash, Cash Equivalents and Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Cash and cash equivalents:
Amortized Cost	$ 79,956	$ 151,570	$ 151,299	$ 143,940
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	79,956	151,570
Investments:
Amortized Cost	108,392	88,846
Gross Unrealized Gains	0	8
Gross Unrealized Losses	(61)	(60)
Fair Value	108,331	88,794
Total cash, cash equivalents and investments, Amortized Cost	188,348	240,416
Total cash, cash equivalents and investments, Gross Unrealized Gains	0	8
Total cash, cash equivalents and investments, Gross Unrealized Losses	(61)	(60)
Total cash, cash equivalents and investments, Fair Value	188,287	240,364
Cash and cash equivalents
Cash and cash equivalents:
Amortized Cost	79,956	151,570
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	79,956	151,570
Commercial paper (due within 1 year)
Investments:
Amortized Cost	55,764	44,122
Gross Unrealized Gains	0	5
Gross Unrealized Losses	(20)	(23)
Fair Value	55,744	44,104
Corporate bonds (due within 1 year)
Investments:
Amortized Cost	52,628	44,724
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(41)	(37)
Fair Value	$ 52,587	$ 44,690