Income Taxes - Additional information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Line Items]
Operating Loss Carry forwards Not Subject To Expiration	$ 23.5
Operating Loss Carryforwards, Limitations on Use Percentage	80.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 0.7	$ 0.2
California Franchise Tax Board [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carry Forwards Expiration Year	2039
Operating Loss Carryforwards	$ 108.2
Domestic Tax Authority [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carry Forwards Expiration Year	2037
Operating Loss Carryforwards	$ 244.8
Domestic Tax Authority [Member] \| Research Tax Credit Carryforward [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carry Forwards Expiration Year	2039
Operating Loss Carryforwards	$ 8.5
State and Local Jurisdiction [Member] \| Research Tax Credit Carryforward [Member]
Income Tax Disclosure [Line Items]
Tax Credit Carryforward, Amount	$ 9.1