Note 4 - Loans/Leases Receivable - Composition of the Loan Lease Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Gross loans/leases receivable	$ 4,251,129	$ 3,690,205
Less allowance	(84,376)	(36,001)	$ (39,847)	$ (34,356)
Net loans/leases receivable	4,166,753	3,654,204
Plus deferred loan/lease origination costs, net of fees.	7,338	8,859
Loans and leases receivable	4,243,791	3,681,346
Commercial Portfolio Segment [Member]
Less allowance	(35,421)	(16,072)	(16,420)	(14,323)
Loans and leases receivable	1,726,723	1,507,825
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans and leases receivable	541,455	378,797
Commercial Real Estate Portfolio Segment [Member]
Less allowance	(42,161)	(15,379)	(17,719)	(13,963)
Loans and leases receivable	2,107,629	1,736,396
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans and leases receivable	541,455	378,797
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Loans and leases receivable	496,471	443,989
Commercial Real Estate Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Loans and leases receivable	1,069,703	913,610
Direct financing leases
Net minimum lease payments to be received	72,940	97,025
Estimated unguaranteed residual values of leased assets	239	547
Unearned lease/residual income	(7,163)	(9,703)
Gross loans/leases receivable	67,088	89,761
Less allowance	(1,764)	(1,464)	(1,792)	(2,382)
Net loans/leases receivable	65,324	88,297
Plus deferred loan/lease origination costs, net of fees.	1,072	1,892
Loans and leases receivable	66,016	87,869
Residential Portfolio Segment [Member]
Less allowance	(3,732)	(1,948)	(2,557)	(2,466)
Loans and leases receivable	252,121	239,904
Residential Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Loans and leases receivable	1,069,703	913,610
Consumer Portfolio Segment [Member]
Less allowance	(1,298)	(1,138)	$ (1,359)	$ (1,222)
Loans and leases receivable	$ 91,302	$ 109,352

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of lease payments to be received by lessor for operating lease.

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The estimate of the value of the leased asset at the end of the lease term.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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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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