Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Cash equivalents
Carrying Value	$ 29,402	$ 47,348
Short-term investments
Amortized Cost	147,670	142,856
Unrealized Gains	21	8
Unrealized Losses	(4)	(13)
Aggregate Fair Value	147,687	142,851
Total marketable securities, Amortized Cost	177,072	190,204
Total marketable securities, Unrealized Gains	21	8
Total marketable securities, Unrealized Losses	(4)	(13)
Total marketable securities, Aggregate Fair Value	177,089	190,199
Money market funds
Cash equivalents
Carrying Value	29,402	45,948
U.S. treasury securities
Short-term investments
Amortized Cost	84,758	74,779
Unrealized Gains	21	4
Unrealized Losses	0	(7)
Aggregate Fair Value	84,779	74,776
Corporate bonds
Short-term investments
Amortized Cost	12,946	8,940
Unrealized Gains	0	4
Unrealized Losses	(4)	(6)
Aggregate Fair Value	12,942	8,938
Commercial paper
Cash equivalents
Carrying Value		1,400
Short-term investments
Amortized Cost	49,966	59,137
Unrealized Gains	0	0
Unrealized Losses	0	0
Aggregate Fair Value	$ 49,966	$ 59,137

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