Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Credit Carryforward [Line Items]
Income tax provision benefit	$ 5,245,000	$ (90,000)	$ 3,000
Period of cumulative changes in ownership interests	3 years
Percentage of cumulative changes in ownership interests	50.00%
Valuation allowance	$ 211,365,000	170,322,000	143,300,000	$ 83,400,000
Increase in valuation allowance	41,100,000	$ 27,000,000.0	$ 59,900,000
Unrecognized tax benefits	0
Alternative minimum tax refund received	800,000
Federal tax authority
Tax Credit Carryforward [Line Items]
Net operating loss carry-forwards	585,400,000
State tax authority
Tax Credit Carryforward [Line Items]
Net operating loss carry-forwards	561,700,000
Foreign tax authority
Tax Credit Carryforward [Line Items]
Net operating loss carry-forwards	$ 98,900,000