Note 12 - Federal and State Income Taxes - Significant Components of Deferred Tax Liabilities and Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred tax liabilities:
Property and equipment	$ 89,960	$ 101,623
Unrealized gains on securities	3,987	3,282
Prepaid expenses and other	2,880	3,303
Total deferred tax liabilities	96,827	108,208
Deferred tax assets:
Current expected credit losses	1,708	1,986
Compensated absences	0	168
Self-insurance allowances	1,063	1,674
Interest	1,509	0
Other	0	49
Total deferred tax assets	4,280	3,877
Net deferred tax liability	$ 92,547	$ 104,331

Amount of deferred tax liability attributable to taxable temporary differences.

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