Cash and Cash Equivalents and Short-Term Investments - Summary of Amortized Cost, Unrealized Gain and Loss and Estimated Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Cash and Cash Equivalents [Line Items]
Amortized Cost	$ 105,485	$ 137,854
Unrealized Gain	149	52
Unrealized Loss	0	(2)
Estimated Fair Value	105,634	137,904
Commercial paper
Cash and Cash Equivalents [Line Items]
Amortized Cost	48,573	61,371
Unrealized Gain	0	0
Unrealized Loss	0	0
Estimated Fair Value	48,573	61,371
Corporate bonds
Cash and Cash Equivalents [Line Items]
Amortized Cost	11,769	23,856
Unrealized Gain	56	14
Unrealized Loss	0	(1)
Estimated Fair Value	11,825	23,869
U.S. Treasury and agency obligations
Cash and Cash Equivalents [Line Items]
Amortized Cost	45,143	52,627
Unrealized Gain	93	38
Unrealized Loss	0	(1)
Estimated Fair Value	45,236	52,664
Money market funds
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	55,178	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	$ 55,178	$ 22,575