Cash and Cash Equivalents and Short-Term Investments - Summary of Amortized Cost, Unrealized Gain and Loss and Estimated Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Cash and Cash Equivalents [Line Items]
Amortized Cost	$ 118,761	$ 137,854
Unrealized Gain	272	52
Unrealized Loss	(109)	(2)
Estimated Fair Value	118,924	137,904
Commercial paper
Cash and Cash Equivalents [Line Items]
Amortized Cost	52,984	61,371
Unrealized Gain	0	0
Unrealized Loss	0	0
Estimated Fair Value	52,984	61,371
Corporate bonds
Cash and Cash Equivalents [Line Items]
Amortized Cost	20,775	23,856
Unrealized Gain	6	14
Unrealized Loss	(109)	(1)
Estimated Fair Value	20,672	23,869
U.S. Treasury and agency obligations
Cash and Cash Equivalents [Line Items]
Amortized Cost	45,002	52,627
Unrealized Gain	266	38
Unrealized Loss	0	(1)
Estimated Fair Value	45,268	52,664
Money market funds
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	40,395	13,588
Commercial paper
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents		8,987
Cash equivalents
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 40,395	$ 22,575