Commitments and Contingencies - Additional Information (Details) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2018 USD ($) ft²	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Contractual arrangements cancellation period				30 days
Rent expenses and common area maintenance charges		$ 0.6	$ 0.6
Rent expense				$ 1.9	$ 1.9
California
Loss Contingencies [Line Items]
Leased premises under non cancelable operating lease | ft²	32,974
Lease term	84 months
Operating lease description				Base rent was abated for the first two months of the lease term and thereafter is $0.2 million per month during the first year of the lease term, with specified annual increases thereafter.
Base rent abated amount	$ 0.2
Lease term extension period		7 years		7 years
California | Minimum [Member]
Loss Contingencies [Line Items]
Lease term extension notice period				9 months
California | Maximum
Loss Contingencies [Line Items]
Lease term extension notice period				12 months
California | Other Non-current Assets
Loss Contingencies [Line Items]
Refundable security deposit		$ 0.4		$ 0.4		$ 0.4