Note 5 - Loans and the Allowance for Credit Losses - Loans by Origination and Risk Designation (Details) - USD ($) $ in Thousands		Sep. 30, 2022	Dec. 31, 2021
Originated Current Fiscal Year		$ 1,680,532	$ 2,134,128
Originated One Year Prior		1,963,543	637,882
Originated Two Years Prior		475,075	517,603
Originated Three Years Prior		434,307	574,284
Originated Four Years Prior		490,162	639,093
Originated Five or More Years Prior		1,374,105	1,103,926
Revolving Loans		1,492,289	1,231,435
Loans and Leases Receivable, Gross		7,910,013	6,838,351
Pass [Member]
Originated Current Fiscal Year		1,672,896	2,131,990
Originated One Year Prior		1,961,452	628,843
Originated Two Years Prior		470,558	511,755
Originated Three Years Prior		417,862	540,362
Originated Four Years Prior		459,658	623,860
Originated Five or More Years Prior		1,278,576	995,049
Revolving Loans		1,456,947	1,176,772
Loans and Leases Receivable, Gross		7,717,949	6,608,631
Special Mention [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		1,905	0
Originated Four Years Prior		0	5,493
Originated Five or More Years Prior		45,397	54,483
Revolving Loans		12,184	12,310
Loans and Leases Receivable, Gross		59,486	72,286
Substandard [Member]
Originated Current Fiscal Year		7,636	2,138
Originated One Year Prior		2,091	9,039
Originated Two Years Prior		4,517	5,848
Originated Three Years Prior		14,540	33,922
Originated Four Years Prior		30,504	9,740
Originated Five or More Years Prior		50,132	54,394
Revolving Loans		23,158	42,353
Loans and Leases Receivable, Gross		132,578	157,434
Doubtful [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Commercial Portfolio Segment [Member]
Originated Current Fiscal Year		256,309	403,373
Originated One Year Prior		311,157	58,534
Originated Two Years Prior		50,818	56,327
Originated Three Years Prior		34,013	73,707
Originated Four Years Prior		66,062	105,468
Originated Five or More Years Prior		190,734	111,625
Revolving Loans		539,634	490,394
Loans and Leases Receivable, Gross	[1]	1,448,727	1,299,428
Commercial Portfolio Segment [Member] | Pass [Member]
Originated Current Fiscal Year		248,673	403,203
Originated One Year Prior		311,005	58,534
Originated Two Years Prior		50,801	54,485
Originated Three Years Prior		31,402	60,409
Originated Four Years Prior		54,872	95,727
Originated Five or More Years Prior		164,539	86,556
Revolving Loans		532,643	471,588
Loans and Leases Receivable, Gross		1,393,935	1,230,502
Commercial Portfolio Segment [Member] | Special Mention [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		588	0
Originated Four Years Prior		0	1
Originated Five or More Years Prior		3,556	4,045
Revolving Loans		3,301	4,266
Loans and Leases Receivable, Gross		7,445	8,312
Commercial Portfolio Segment [Member] | Substandard [Member]
Originated Current Fiscal Year		7,636	170
Originated One Year Prior		152	0
Originated Two Years Prior		17	1,842
Originated Three Years Prior		2,023	13,298
Originated Four Years Prior		11,190	9,740
Originated Five or More Years Prior		22,639	21,024
Revolving Loans		3,690	14,540
Loans and Leases Receivable, Gross		47,347	60,614
Commercial Portfolio Segment [Member] | Doubtful [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Commercial Real Estate Portfolio Segment [Member]
Originated Current Fiscal Year		1,386,412	1,694,066
Originated One Year Prior		1,619,294	542,354
Originated Two Years Prior		391,635	425,001
Originated Three Years Prior		378,054	472,886
Originated Four Years Prior		403,602	502,207
Originated Five or More Years Prior		1,099,819	918,790
Revolving Loans		388,032	186,286
Loans and Leases Receivable, Gross		5,666,848	4,741,590
Commercial Real Estate Portfolio Segment [Member] | Pass [Member]
Originated Current Fiscal Year		1,386,412	1,692,098
Originated One Year Prior		1,617,355	533,315
Originated Two Years Prior		387,135	420,995
Originated Three Years Prior		364,220	452,262
Originated Four Years Prior		384,288	497,065
Originated Five or More Years Prior		1,033,994	842,244
Revolving Loans		370,982	170,721
Loans and Leases Receivable, Gross		5,544,386	4,608,700
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		1,317	0
Originated Four Years Prior		0	5,142
Originated Five or More Years Prior		41,841	50,438
Revolving Loans		8,883	6,601
Loans and Leases Receivable, Gross		52,041	62,181
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member]
Originated Current Fiscal Year		0	1,968
Originated One Year Prior		1,939	9,039
Originated Two Years Prior		4,500	4,006
Originated Three Years Prior		12,517	20,624
Originated Four Years Prior		19,314	0
Originated Five or More Years Prior		23,984	26,108
Revolving Loans		8,167	8,964
Loans and Leases Receivable, Gross		70,421	70,709
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Commercial Construction Portfolio Segment [Member]
Originated Current Fiscal Year		2,056	8,018
Originated One Year Prior		7,605	7,370
Originated Two Years Prior		7,320	12,625
Originated Three Years Prior		508	2,600
Originated Four Years Prior		0	2,689
Originated Five or More Years Prior		0	0
Revolving Loans		519,834	506,876
Loans and Leases Receivable, Gross		537,323	540,178
Commercial Construction Portfolio Segment [Member] | Pass [Member]
Originated Current Fiscal Year		2,056	8,018
Originated One Year Prior		7,605	7,370
Originated Two Years Prior		7,320	12,625
Originated Three Years Prior		508	2,600
Originated Four Years Prior		0	2,339
Originated Five or More Years Prior		0	0
Revolving Loans		512,107	490,119
Loans and Leases Receivable, Gross		529,596	523,071
Commercial Construction Portfolio Segment [Member] | Special Mention [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	350
Originated Five or More Years Prior		0	0
Revolving Loans		0	1,443
Loans and Leases Receivable, Gross		0	1,793
Commercial Construction Portfolio Segment [Member] | Substandard [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		7,727	15,314
Loans and Leases Receivable, Gross		7,727	15,314
Commercial Construction Portfolio Segment [Member] | Doubtful [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Residential Portfolio Segment [Member]
Originated Current Fiscal Year		34,852	27,081
Originated One Year Prior		25,487	29,539
Originated Two Years Prior		25,292	23,611
Originated Three Years Prior		21,732	25,070
Originated Four Years Prior		20,493	28,701
Originated Five or More Years Prior		83,551	73,511
Revolving Loans		44,678	47,756
Loans and Leases Receivable, Gross		256,085	255,269
Residential Portfolio Segment [Member] | Pass [Member]
Originated Current Fiscal Year		34,852	27,081
Originated One Year Prior		25,487	29,539
Originated Two Years Prior		25,292	23,611
Originated Three Years Prior		21,732	25,070
Originated Four Years Prior		20,493	28,701
Originated Five or More Years Prior		80,042	66,249
Revolving Loans		41,104	44,221
Loans and Leases Receivable, Gross		249,002	244,472
Residential Portfolio Segment [Member] | Special Mention [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Residential Portfolio Segment [Member] | Substandard [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		3,509	7,262
Revolving Loans		3,574	3,535
Loans and Leases Receivable, Gross		7,083	10,797
Residential Portfolio Segment [Member] | Doubtful [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Consumer Portfolio Segment [Member]
Originated Current Fiscal Year		903	1,590
Originated One Year Prior		0	85
Originated Two Years Prior		10	39
Originated Three Years Prior		0	21
Originated Four Years Prior		5	28
Originated Five or More Years Prior		1	0
Revolving Loans		111	123
Loans and Leases Receivable, Gross		1,030	1,886
Consumer Portfolio Segment [Member] | Pass [Member]
Originated Current Fiscal Year		903	1,590
Originated One Year Prior		0	85
Originated Two Years Prior		10	39
Originated Three Years Prior		0	21
Originated Four Years Prior		5	28
Originated Five or More Years Prior		1	0
Revolving Loans		111	123
Loans and Leases Receivable, Gross		1,030	1,886
Consumer Portfolio Segment [Member] | Special Mention [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Consumer Portfolio Segment [Member] | Substandard [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		0	0
Consumer Portfolio Segment [Member] | Doubtful [Member]
Originated Current Fiscal Year		0	0
Originated One Year Prior		0	0
Originated Two Years Prior		0	0
Originated Three Years Prior		0	0
Originated Four Years Prior		0	0
Originated Five or More Years Prior		0	0
Revolving Loans		0	0
Loans and Leases Receivable, Gross		$ 0	$ 0

[1] Includes PPP loans of $11.5 million and $93.1 million as of September 30, 2022 and December 31, 2021 , respectively.