Short-Term Investments - Summary of Investments Included in Cash Equivalents and Short Term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	$ 261,955	$ 214,343
Cash equivalents and short-term investments, Unrealized Gains	183
Cash equivalents and short-term investments, Unrealized Losses	0	(77)
Cash equivalents and short-term investments, Fair Value	262,138	214,266
Money Market Mutual Funds
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	39,524	31,740
Cash equivalents and short-term investments, Fair Value	39,524	31,740
Repurchase Agreements
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	14,000
Cash equivalents and short-term investments, Fair Value	14,000
Asset-backed Securities
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	14,866	19,541
Cash equivalents and short-term investments, Unrealized Gains	10
Cash equivalents and short-term investments, Unrealized Losses		(21)
Cash equivalents and short-term investments, Fair Value	14,876	19,520
Commercial Paper
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	41,259	78,571
Cash equivalents and short-term investments, Fair Value	41,259	78,571
Corporate Debt Securities
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	92,380	54,511
Cash equivalents and short-term investments, Unrealized Gains	128
Cash equivalents and short-term investments, Unrealized Losses		(50)
Cash equivalents and short-term investments, Fair Value	92,508	54,461
U.S Treasury Securities
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items]
Cash equivalents and short-term investments, Amortized Cost	59,926	29,980
Cash equivalents and short-term investments, Unrealized Gains	45
Cash equivalents and short-term investments, Unrealized Losses		(6)
Cash equivalents and short-term investments, Fair Value	$ 59,971	$ 29,974