Fair Value of Financial Instruments (Details)	9 Months Ended
	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	$ 0
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	31,242,000	$ 25,704,000
Short-term investments	$ 179,995,000	204,164,000
Measurement Input, Revenue Volatility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability, unobservable inputs	0.1200
Measurement Input, Risk Free Interest Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability, unobservable inputs	0.0013
U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments		3,000,000
Corporate debt securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	$ 172,498,000	188,310,000
Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	186,697,000	208,250,000
Contingent consideration	2,170,000	0
Total liabilities measured at fair value	2,170,000	0
Fair Value, Measurements, Recurring | Level 1
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	6,702,000	4,086,000
Contingent consideration	0	0
Total liabilities measured at fair value	0	0
Fair Value, Measurements, Recurring | Level 2
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	179,995,000	204,164,000
Contingent consideration	0	0
Total liabilities measured at fair value	0	0
Fair Value, Measurements, Recurring | Level 3
Assets, Fair Value Disclosure [Abstract]
Contingent consideration	2,170,000	0
Total liabilities measured at fair value	2,170,000	0
Fair Value, Measurements, Recurring | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	3,000,000
Fair Value, Measurements, Recurring | U.S. government agency securities | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | U.S. government agency securities | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	3,000,000
Fair Value, Measurements, Recurring | Corporate debt securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	172,498,000	188,310,000
Fair Value, Measurements, Recurring | Corporate debt securities | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | Corporate debt securities | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	172,498,000	188,310,000
Fair Value, Measurements, Recurring | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	6,702,000	4,086,000
Fair Value, Measurements, Recurring | Money market funds | Level 1
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	6,702,000	4,086,000
Fair Value, Measurements, Recurring | Money market funds | Level 2
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Fair Value, Measurements, Recurring | Commercial paper
Assets, Fair Value Disclosure [Abstract]
Short-term investments	7,497,000	12,854,000
Fair Value, Measurements, Recurring | Commercial paper | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | Commercial paper | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	$ 7,497,000	$ 12,854,000