Note 4 - Loans - Allowance for Credit Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Dec. 31, 2019
Balance	$ 12,231	$ 12,292
Charge-offs	(169)	(348)
Recoveries	155	298
Provision for loan and lease losses	2,850
Balance	15,067	12,242
Individually evaluated for impairment			$ 318	$ 324
Collectively evaluated for impairment			14,749	11,907
Total	15,067	12,242	15,067	12,231
Individually evaluated for impairment			9,952	10,399
Collectively evaluated for impairment			1,042,293	1,022,504
Total gross loans			1,052,245	1,032,903
Commercial Portfolio Segment [Member]
Balance	1,822	2,205
Charge-offs
Recoveries	7	153
Provision for loan and lease losses	654	121
Balance	2,483	2,479
Individually evaluated for impairment			160	159
Collectively evaluated for impairment			2,323	1,663
Total	2,483	2,479	2,483	1,822
Individually evaluated for impairment			631	656
Collectively evaluated for impairment			138,239	140,541
Total gross loans			138,870	141,197
Commercial Real Estate Portfolio Segment [Member]
Balance	8,096	7,116
Charge-offs
Recoveries
Provision for loan and lease losses	1,803	(160)
Balance	9,899	6,956
Individually evaluated for impairment
Collectively evaluated for impairment			9,899	8,096
Total	9,899	6,956	9,899	8,096
Individually evaluated for impairment			3,103	3,103
Collectively evaluated for impairment			762,662	736,480
Total gross loans			765,765	739,583
Residential Portfolio Segment [Member]
Balance	1,032	1,173
Charge-offs	(6)	(68)
Recoveries	44	82
Provision for loan and lease losses	211	24
Balance	1,281	1,211
Individually evaluated for impairment			148	154
Collectively evaluated for impairment			1,133	878
Total	1,281	1,211	1,281	1,032
Individually evaluated for impairment			6,179	6,600
Collectively evaluated for impairment			111,510	112,199
Total gross loans			117,689	118,799
Consumer Portfolio Segment [Member]
Balance	933	1,356
Charge-offs	(163)	(280)
Recoveries	104	63
Provision for loan and lease losses	98	(83)
Balance	972	1,056
Individually evaluated for impairment			10	11
Collectively evaluated for impairment			962	922
Total	972	1,056	972	933
Individually evaluated for impairment			39	40
Collectively evaluated for impairment			29,882	33,284
Total gross loans			29,921	33,324
Unallocated Financing Receivables [Member]
Balance	348	442
Charge-offs
Recoveries
Provision for loan and lease losses	84	98
Balance	432	540
Individually evaluated for impairment
Collectively evaluated for impairment			432	348
Total	$ 432	$ 540	432	348
Individually evaluated for impairment
Collectively evaluated for impairment
Total gross loans

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 increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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

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Amount of expense related to estimated loss from loan and lease transactions.

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