Note 5 - Other Assets - Summary of Major Components of Other Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Cash surrender value of life insurance other than BOLI	$ 18,913	$ 18,426
Net deferred tax asset	24,629	22,320
Investments in tax credit related ventures	9,400	9,552
Swap assets	4,080	8,374
Prepaid assets	2,267	2,935
Trust fees receivable	2,350	2,192
Mortgage servicing rights	2,865	2,710	$ 1,446	$ 1,372
Other real estate owned	281	281
Other	5,013	4,575
Total other assets	$ 69,798	$ 71,365

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount of assets classified as other.

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Amount of other miscellaneous assets.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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