Note 13 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Deferred Tax Assets, Valuation Allowance	$ 0	$ 0
Provision for income taxes	35,851,000	65,905,000	$ 75,361,000
Deferred Income Tax Liabilities, Net	232,398,000	197,068,000
Texas Margin Tax [Member]
Provision for income taxes	469,000	0	0
Texas Margin Tax [Member] | State and Local Jurisdiction [Member]
Deferred Income Tax Liabilities, Net	8,600,000	$ 7,100,000
Cumulative Effect, Period of Adoption, Adjustment [Member]
Provision for income taxes	1,000,000
Deferred Tax Assets, Gross	$ 3,000,000		$ 3,400,000