Income Taxes (Details Textuals) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Valuation Allowance [Line Items]
Valuation allowance	$ 129,408,000	$ 77,215,000
Federal net operating loss carryforwards	0
Business interest expense carryforward	0	24,513,000
Business credit carryforwards	0	71,555,000
Alternative minimum tax credits	600,000
Loss and tax credit carryforwards - state	55,979,000	$ 52,917,000
Unrecognized tax benefits	0
Income tax interest or penalties	0
Louisiana, Mississippi, Montana, North Dakota and Alabama
Valuation Allowance [Line Items]
State deferred tax assets	75,100,000
Valuation allowance	$ 75,100,000

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible interest carryforward.

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