Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Income Tax [Line Items]
Deferred tax asset, valuation allowance eliminated	$ (3,344,000,000)		$ (3,344,000,000)
Net balance of deferred tax asset		$ 3,500,000
Deferred tax asset, valuation allowance		$ 379,000	$ 388,000
Earliest Tax Year [Member]
Income Tax [Line Items]
Tax credit carryforwards expiration year		2037
Tax credits expiration year		2021
Latest Tax Year [Member]
Income Tax [Line Items]
Tax credit carryforwards expiration year		2047
Tax credits expiration year		2025
Research and Development Credit Carryforwards [Member]
Income Tax [Line Items]
Tax credit carryforward amount		$ 1,717,000
Research and Development Credit Carryforwards [Member] | Earliest Tax Year [Member]
Income Tax [Line Items]
Tax credit carryforwards expiration year		2021
Research and Development Credit Carryforwards [Member] | Latest Tax Year [Member]
Income Tax [Line Items]
Tax credit carryforwards expiration year		2039
Federal [Member]
Income Tax [Line Items]
Net operating loss carryforwards		$ 4,254,000
Operating loss carryforwards expiration year		2038
State [Member]
Income Tax [Line Items]
Net operating loss carryforwards		$ 5,815,000