Note 4 - Loans/Leases Receivable - Aging of the Loan Lease Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current	$ 4,225,516	$ 3,659,453
Accruing Past Due 90 Days or More	3	33
Financing Receivable, Recorded Investment, Nonaccrual Status	13,940	7,902
Loans and leases	$ 4,243,791	$ 3,681,346
Current as a percentage of total loan/lease portfolio	99.57%	99.41%
Accruing past due 90 days or more as a percentage of total loan/lease portfolio	0.00%	0.00%
Nonaccrual Loans/Leases as a percentage of total loan/lease portfolio	0.33%	0.21%
Loans and leases as a percentage of total loan/lease portfolio	100.00%	100.00%
Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	$ 3,591	$ 12,638
Past due as a percentage of total loan/lease portfolio	0.08%	0.34%
Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	$ 741	$ 1,320
Past due as a percentage of total loan/lease portfolio	0.02%	0.04%
Commercial Portfolio Segment [Member]
Current	$ 1,720,058	$ 1,499,891
Financing Receivable, Recorded Investment, Nonaccrual Status	4,807	1,236
Loans and leases	1,726,723	1,507,825
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans and leases	541,455	378,797
Commercial Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	1,535	6,126
Commercial Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	323	572
Commercial Real Estate Portfolio Segment [Member]
Loans and leases	2,107,629	1,736,396
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Current	496,459	443,707
Financing Receivable, Recorded Investment, Nonaccrual Status	12	34
Loans and leases	496,471	443,989
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Current	541,455	375,940
Loans and leases	541,455	378,797
Commercial Real Estate Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Current	1,062,215	909,684
Financing Receivable, Recorded Investment, Nonaccrual Status	7,488	3,853
Loans and leases	1,069,703	913,610
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Past Due		177
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Construction Loans [Member]
Past Due		2,857
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Past Due		73
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Past Due		71
Direct financing leases
Current	64,918	85,636
Financing Receivable, Recorded Investment, Nonaccrual Status	406	1,517
Loans and leases	66,016	87,869
Direct financing leases \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	501	463
Direct financing leases \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	191	253
Residential Portfolio Segment [Member]
Current	249,364	235,845
Financing Receivable, Recorded Investment, Nonaccrual Status	1,022	706
Loans and leases	252,121	239,904
Residential Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Loans and leases	1,069,703	913,610
Residential Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	1,512	2,939
Residential Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	223	414
Consumer Portfolio Segment [Member]
Current	91,047	108,750
Accruing Past Due 90 Days or More	3	33
Financing Receivable, Recorded Investment, Nonaccrual Status	205	556
Loans and leases	91,302	109,352
Consumer Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past Due	43	3
Consumer Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past Due	$ 4	$ 10

Reflects the percentage derived from dividing loans accruing past due 90 days or more by total loans.

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Reflects the percentage derived from dividing current loans by total loans.

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Reflects the percentage derived from dividing nonaccrual loans by total loans.

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Reflects the percentage derived from dividing past due loans by total loans.

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Amount of financing receivable 90 days or more past due and still accruing.

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Amount of financing receivable not past due.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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