Note 4 - Loans/Leases Receivable - Loans Leases Nonperforming Loans Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accruing Past Due 90 Days or More	$ 3	$ 33
Nonaccrual Loans/Leases	13,940	7,902
Accruing TDRs	1,700	1,700
Loans and Leases Receivable, Net of Deferred Income	$ 4,243,791	$ 3,681,346
Percentage of Total NPLs	100.00%	100.00%
Nonperforming Financial Instruments [Member]
Accruing Past Due 90 Days or More	$ 3	$ 33
Nonaccrual Loans/Leases	13,940	7,902
Accruing TDRs	741	979
Loans and Leases Receivable, Net of Deferred Income	$ 14,684	$ 8,914
Percentage of Total NPLs	100.00%	100.00%
Commercial Portfolio Segment [Member]
Nonaccrual Loans/Leases	$ 4,807	$ 1,236
Loans and Leases Receivable, Net of Deferred Income	1,726,723	1,507,825
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans and Leases Receivable, Net of Deferred Income	541,455	378,797
Commercial Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual Loans/Leases	4,807	1,236
Accruing TDRs	606	646
Loans and Leases Receivable, Net of Deferred Income	$ 5,413	$ 1,882
Percentage of Total NPLs	36.87%	21.12%
Commercial Real Estate Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income	$ 2,107,629	$ 1,736,396
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	12	34
Loans and Leases Receivable, Net of Deferred Income	496,471	443,989
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans and Leases Receivable, Net of Deferred Income	541,455	378,797
Commercial Real Estate Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	7,488	3,853
Loans and Leases Receivable, Net of Deferred Income	1,069,703	913,610
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	12	34
Loans and Leases Receivable, Net of Deferred Income	$ 12	$ 34
Percentage of Total NPLs	0.08%	0.38%
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Nonaccrual Loans/Leases	$ 7,488	$ 3,853
Loans and Leases Receivable, Net of Deferred Income	$ 7,488	$ 3,853
Percentage of Total NPLs	50.99%	43.22%
Direct financing leases
Nonaccrual Loans/Leases	$ 406	$ 1,517
Loans and Leases Receivable, Net of Deferred Income	66,016	87,869
Direct financing leases \| Nonperforming Financial Instruments [Member]
Nonaccrual Loans/Leases	406	1,517
Accruing TDRs	135	333
Loans and Leases Receivable, Net of Deferred Income	$ 541	$ 1,850
Percentage of Total NPLs	3.68%	20.75%
Residential Portfolio Segment [Member]
Nonaccrual Loans/Leases	$ 1,022	$ 706
Loans and Leases Receivable, Net of Deferred Income	252,121	239,904
Residential Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Loans and Leases Receivable, Net of Deferred Income	1,069,703	913,610
Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual Loans/Leases	1,022	706
Loans and Leases Receivable, Net of Deferred Income	$ 1,022	$ 706
Percentage of Total NPLs	6.96%	7.92%
Consumer Portfolio Segment [Member]
Accruing Past Due 90 Days or More	$ 3	$ 33
Nonaccrual Loans/Leases	205	556
Loans and Leases Receivable, Net of Deferred Income	91,302	109,352
Consumer Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Accruing Past Due 90 Days or More	3	33
Nonaccrual Loans/Leases	205	556
Loans and Leases Receivable, Net of Deferred Income	$ 208	$ 589
Percentage of Total NPLs	1.42%	6.61%

Amount of financing receivable modified as troubled debt restructuring.

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