Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax [Line Items]
Deferred tax asset, valuation allowance	$ 71,159,000	$ 46,578,000
Number of years cumulative pre-tax loss	3 years
Indefinite-lived intangible assets	$ 0
Unrecognized tax benefits	2,452,000	$ 4,334,000	$ 4,440,000
Accrued interest and penalties	0
Operating loss carryforwards state	205,200,000
Operating loss carryforwards federal	128,200,000
Federal and state net operating loss carryforwards, expiring year		2039
State research and development tax credit carryforwards	$ 3,200,000
Cumulative change in ownership percentage	50.00%
Period for cumulative change in ownership	3 years
Federal
Income Tax [Line Items]
Deferred tax asset, valuation allowance increase (decrease)	$ 20,100,000
State
Income Tax [Line Items]
Deferred tax asset, valuation allowance increase (decrease)	$ 4,500,000