Note 18 - Stockholders' Equity - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Beginning balance, loss, net of tax	$ 2,542,339	$ 2,422,230	$ 2,474,040	$ 2,446,251
Total other comprehensive (loss)/income, net of tax	(7,972)	(25,351)	3,246	(68,263)
Ending balance, loss, net of tax	2,602,671	2,431,532	2,602,671	2,431,532
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Beginning balance, loss, net of tax	(93,173)	(45,755)	(104,832)	211
Net unrealized (losses)/gains arising during the period, pre-tax	(10,691)	(37,557)	5,860	(102,812)
Net unrealized (losses)/gains arising during the period, tax	(3,160)	(11,102)	1,732	(30,391)
Net unrealized (losses)/gains arising during the period, net of tax	(7,531)	(26,455)	4,128	(72,421)
Reclassification adjustment for net losses/(gains) included in net income, pre-tax	0	0	0	0
Reclassification adjustment for net losses/(gains) included in net income, tax	0	0	0	0
Reclassification adjustment for net losses/(gains) included in net income, net of tax	0	0	0	0
Total other comprehensive (loss)/income, pre-tax	(10,691)	(37,557)	5,860	(102,812)
Total other comprehensive (loss)/income, tax	(3,160)	(11,102)	1,732	(30,391)
Total other comprehensive (loss)/income, net of tax	(7,531)	(26,455)	4,128	(72,421)
Ending balance, loss, net of tax	(100,704)	(72,210)	(100,704)	(72,210)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Beginning balance, loss, net of tax	2,096	(222)	2,537	(3,276)
Net unrealized (losses)/gains arising during the period, pre-tax	(626)	1,567	(1,252)	5,903
Net unrealized (losses)/gains arising during the period, tax	(185)	463	(370)	1,745
Net unrealized (losses)/gains arising during the period, net of tax	(441)	1,104	(882)	4,158
Reclassification adjustment for net losses/(gains) included in net income, pre-tax	0	0	0	0
Reclassification adjustment for net losses/(gains) included in net income, tax	0	0	0	0
Reclassification adjustment for net losses/(gains) included in net income, net of tax	0	0	0	0
Total other comprehensive (loss)/income, pre-tax	(626)	1,567	(1,252)	5,903
Total other comprehensive (loss)/income, tax	(185)	463	(370)	1,745
Total other comprehensive (loss)/income, net of tax	(441)	1,104	(882)	4,158
Ending balance, loss, net of tax	1,655	882	1,655	882
AOCI Attributable to Parent [Member]
Beginning balance, loss, net of tax	(91,077)	(45,977)	(102,295)	(3,065)
Net unrealized (losses)/gains arising during the period, pre-tax	(11,317)	(35,990)	4,608	(96,909)
Net unrealized (losses)/gains arising during the period, tax	(3,345)	(10,639)	1,362	(28,646)
Net unrealized (losses)/gains arising during the period, net of tax	(7,972)	(25,351)	3,246	(68,263)
Reclassification adjustment for net losses/(gains) included in net income, pre-tax	0	0	0	0
Reclassification adjustment for net losses/(gains) included in net income, tax	0	0	0	0
Reclassification adjustment for net losses/(gains) included in net income, net of tax	0	0	0	0
Total other comprehensive (loss)/income, pre-tax	(11,317)	(35,990)	4,608	(96,909)
Total other comprehensive (loss)/income, tax	(3,345)	(10,639)	1,362	(28,646)
Total other comprehensive (loss)/income, net of tax	(7,972)	(25,351)	3,246	(68,263)
Ending balance, loss, net of tax	$ (99,049)	$ (71,328)	$ (99,049)	$ (71,328)