Note 7 - Comprehensive (Loss) Income - Reclassification out of Accumulated Other Comprehensive (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Interest income (expense) on cash flow hedges	$ 67,084	$ 70,358
Income tax expense	9,077	11,351
Net income	24,929	31,381
Other components of net periodic pension expense	(25)	(143)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Net income	2,932	(390)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Interest income (expense) on cash flow hedges	4,267	(525)
Income tax expense	23	4
Net income	(51)	(12)
Reclassification out of Accumulated Other Comprehensive Income [Member] | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Income tax expense	(1,284)	147
Net income	2,983	(378)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Other components of net periodic pension expense	$ (74)	$ (16)