Cash Equivalents and Short-Term Investments - Summary of Cash Equivalents and Short-Term Investments (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Cash And Cash Equivalents [Line Items]
Cash equivalents, Fair Value		$ 41,381,000
Cash equivalents and short-term investments, Amortized Cost Basis		97,650,000
Cash equivalents and short-term investments, Unrealized Gains		36,000
Cash equivalents and short-term investments, Unrealized losses		(1,000)
Cash equivalents and short-term investments, Fair Value		97,685,000
Short-term investments		56,304,000
U.S. Treasury securities
Cash And Cash Equivalents [Line Items]
Short-term investments Amortized Cost Basis		43,219,000
Short-term investments Unrealized Gains		27,000
Short-term investments Unrealized Losses		(1,000)
Short-term investments, Fair Value		43,245,000
Reverse Repurchase Agreements
Cash And Cash Equivalents [Line Items]
Short-term investments Amortized Cost Basis		10,000,000
Short-term investments, Fair Value		10,000,000
Commercial paper
Cash And Cash Equivalents [Line Items]
Short-term investments Amortized Cost Basis		6,958,000
Short-term investments, Fair Value		6,958,000
Corporate bonds
Cash And Cash Equivalents [Line Items]
Short-term investments Amortized Cost Basis		8,087,000
Short-term investments Unrealized Gains		9,000
Short-term investments, Fair Value		8,096,000
Money Market Funds
Cash And Cash Equivalents [Line Items]
Cash equivalents Amortized Cost Basis		29,386,000
Cash equivalents Unrealized Gains	$ 0
Cash equivalents Unrealized Losses	0
Cash equivalents, Fair Value	$ 213,300,000	$ 29,386,000