Note 2 - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual) - USD ($)		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Accounts Receivable, after Allowance for Credit Loss, Current		$ 71,425,000		$ 71,425,000		$ 85,242,000
Income Taxes Receivable		3,100,000		3,100,000		3,100,000
Accounts Payable and Accrued Liabilities, Current		140,700,000		140,700,000		284,600,000
Oil and Gas, Joint Interest Billing, Receivable		2,600,000		2,600,000		4,700,000
Accounts Receivable, Allowance for Credit Loss		0		0		0
Inventory, Raw Materials and Supplies, Gross		6,800,000		6,800,000		11,000,000
Prepaid Expense		4,800,000		4,800,000		4,600,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment		1,200,000		1,200,000		1,100,000
Payments of Debt Issuance Costs				(0)	$ 58,000
Amortization of Debt Issuance Costs				4,091,000	4,119,000
Debt Instrument, Unamortized Discount	[1]	12,318,000		12,318,000		17,197,000
Amortization of Debt Discount (Premium)				4,879,000	4,906,000
Income Tax Expense (Benefit)		7,663,000	$ 14,250,000	17,602,000	16,547,000
Texas Margin Tax [Member]
Income Tax Expense (Benefit)				0	301,000
Flood [Member]
Unusual or Infrequent Item, or Both, Cost of Repairs			$ 2,000,000		2,000,000
Debt Refinancing Expenses [Member]
Professional Fees		2,500,000		$ 2,500,000
Minimum [Member]
Oil and Natural Gas Marketing Contracts, Term Over Which Consideration is Received from Purchaser				1 month
Maximum [Member]
Oil and Natural Gas Marketing Contracts, Term Over Which Consideration is Received from Purchaser				2 months
Senior Unsecured Notes and Revolving Credit Facility [Member]
Debt Issuance Costs, Gross		25,100,000		$ 25,100,000
Payments of Debt Issuance Costs				0		$ 58,000
Amortization of Debt Issuance Costs				4,100,000	4,100,000
Senior Unsecured Notes Due 2024 [Member]
Debt Instrument, Unamortized Discount		$ 30,000,000		30,000,000
Amortization of Debt Discount (Premium)				$ 4,900,000	$ 4,900,000
Transportation Equipment [Member]
Property, Plant and Equipment, Useful Life		5 years		5 years
Building [Member]
Property, Plant and Equipment, Useful Life		40 years		40 years
Field Equipment [Member]
Property, Plant and Equipment, Useful Life		7 years		7 years
Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life		5 years		5 years
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Largest Purchaser [Member]
Concentration Risk, Percentage				87.00%		76.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Second Largest Purchaser [Member]
Concentration Risk, Percentage				10.00%		18.00%
Electric Power Infrastructure [Member]
Accounts Payable and Accrued Liabilities, Current		$ 2,700,000		$ 2,700,000		$ 1,400,000
Crude Oil, Natural Gas and Natural Gas Liquids [Member]
Accounts Receivable, after Allowance for Credit Loss, Current		63,000,000		63,000,000		76,000,000
Aid-in-construction Receivables [Member] | WTG Gas Processing, L.P. [Member]
Contract with Customer, Asset, after Allowance for Credit Loss		$ 17,200,000		17,200,000		18,000,000
Aid-in-construction [Member] | WTG Gas Processing, L.P. [Member]
Contract with Customer, Asset, Asset Funding				71,000		17,500,000
Contract with Customer, Asset, Payments Received				$ 878,000		$ 2,000,000

[1] Discounts as of June 30, 2025 and December 31, 2024 consisted of $30.0 million in discounts less accumulated amortization of $17.7 million and $12.8 million, respectively.