Note 13 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Deferred Tax Assets, Valuation Allowance	$ 0		$ 0		$ 0
Income Tax Expense (Benefit)	14,250,000	$ 9,644,000	16,547,000	$ 24,151,000
Deferred Income Tax Liabilities, Net	213,038,000		213,038,000		197,068,000
Texas Margin Tax [Member]
Income Tax Expense (Benefit)			301,000	$ 0
Texas Margin Tax [Member] | State and Local Jurisdiction [Member]
Deferred Income Tax Liabilities, Net	7,700,000		7,700,000		$ 7,100,000
Cumulative Effect, Period of Adoption, Adjustment [Member]
Income Tax Expense (Benefit)			1,000,000
Deferred Tax Assets, Gross	$ 3,000,000		$ 3,000,000