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Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
Statutory federal income tax rate	21.00%	21.00%	21.00%
Possible decrease in unrecognized tax benefits	$ 3,500,000
Uncertain tax position, accrued interest	7,600,000	$ 6,100,000	$ 0
Federal
Income Taxes [Line Items]
Operating loss carryforwards	64,100,000
Obligations of states and state agencies
Income Taxes [Line Items]
Operating loss carryforwards	92,200,000
Capital loss carryforward
Income Taxes [Line Items]
Capital loss carryforwards	$ 3,100,000