Fair Value of Financial Assets - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	$ 91,396	$ 153,660
Cash Equivalents | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	30,490	77,737
Cash Equivalents | U.S. Government Agency Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	2,500
Marketable Securities | U.S. Treasury Notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	42,868	62,842
Marketable Securities | U.S. Government Agency Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	15,538	2,885
Marketable Securities | Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis		10,196
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	30,490	77,737
Level 1 | Cash Equivalents | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	30,490	77,737
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	60,906	75,923
Level 2 | Cash Equivalents | U.S. Government Agency Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	2,500
Level 2 | Marketable Securities | U.S. Treasury Notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	42,868	62,842
Level 2 | Marketable Securities | U.S. Government Agency Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis	$ 15,538	2,885
Level 2 | Marketable Securities | Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured on recurring basis		$ 10,196