Note 4 - Loans/Leases Receivable (Details)	12 Months Ended
Dec. 31, 2020 USD ($) item lease loan state	Dec. 31, 2019 USD ($) lease contract item	Dec. 31, 2018 USD ($)
Loans and leases	$ 4,243,791,000	$ 3,681,346,000
Loans receivable held for sale	3,758,000	3,673,000
Nonaccrual Loans/Leases	13,940,000	7,902,000
Accruing TDRs	1,700,000	1,700,000
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 1,022,000	$ 1,093,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	1	2
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	$ 44,000	$ 66,000
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 266,000	$ 52,000
Number of Loans / Leases	4,000	15,000
Number of TDRs restructured and written off \| item	5	1
Threshold for Related Party Loans Evaluated	$ 60,000	$ 60,000	$ 60,000
Accruing TDRs	1,700,000	1,700,000
Accruing Past Due 90 Days or More	$ 3,000	33,000
Financing Receivable, Modification, Number of Contracts	197,000,000
Financing Receivable, Loan Modification, Not Treated as Troubled Debt Restructuring	$ 28,000,000
Number of states holding investments \| state	50
m2 Lease Funds, LLC
Financing Receivable, Loan Modification, Not Treated as Troubled Debt Restructuring	$ 7,000,000
Loan Relief Program
Financing Receivable, Modification, Number of Contracts	126
Financing Receivable, Loan Modification, Not Treated as Troubled Debt Restructuring	$ 21,000,000
Financial Receivables Loan Modification, Percent	0.66%
Nonaccrual [Member]
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 880,000	$ 121,000
Number of Loans / Leases	2	3
Troubled Debt Restructurings [Member]
Nonaccrual Loans/Leases	$ 984,000
Accruing Past Due 90 Days or More		$ 747,000
Residential Portfolio Segment [Member]
Loans and leases	252,121,000	239,904,000
Financing Receivable, Held-for-Sale	3,800,000	3,700,000
Nonaccrual Loans/Leases	1,022,000	706,000
Residential Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Accruing Past Due 90 Days or More		31,000
Commercial Portfolio Segment [Member]
Loans and leases	1,726,723,000	1,507,825,000
Nonaccrual Loans/Leases	4,807,000	1,236,000
Commercial Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Accruing Past Due 90 Days or More		98,000
Commercial Portfolio Segment [Member] \| m2 Lease Funds, LLC
Loans and leases	171,500,000	142,000,000.0
Commercial Real Estate Portfolio Segment [Member]
Loans and leases	2,107,629,000	1,736,396,000
Commercial Real Estate Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Nonaccrual Loans/Leases	$ 836,000
Accruing Past Due 90 Days or More		269,000
Direct financing leases
Number of Leases \| lease	3
Loss related to unguaranteed residual values of leases	$ 0	0	$ 0
Loans and leases	66,016,000	87,869,000
Nonaccrual Loans/Leases	406,000	1,517,000
Direct financing leases \| Troubled Debt Restructurings [Member]
Nonaccrual Loans/Leases	100,000
Accruing Past Due 90 Days or More		294,000
Consumer Portfolio Segment [Member]
Loans and leases	91,302,000	109,352,000
Nonaccrual Loans/Leases	205,000	556,000
Accruing Past Due 90 Days or More	3,000	33,000
Consumer Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Nonaccrual Loans/Leases	48,000
Accruing Past Due 90 Days or More		$ 55,000
No Lease End Option Rider [Member] \| Direct financing leases
Number of Leases \| lease		6
Lease residual values	$ 239,000	$ 547,000

The percent of financial receivable loans modified and not treated as troubled debt restructuring.

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Amount of financing receivable modified not treated as troubled debt restructuring.

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Number of financing receivables that have been modified and not treated as troubled debt restructuring.

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The amount of losses related to unguaranteed residual values of leases.

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The number of leases.

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Represents the number of states investments are held in.

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The number of trouble debt restructurings restructured and written off.

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The threshold amount for related party loans evaluated.

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Amount of residual asset covered by residual value guarantee under direct financing lease. Excludes guarantee considered to be lease payments for lessor.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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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 on nonaccrual status.

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Reflects the amount of the write-down related to a troubled debt restructuring.

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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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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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