Note 5 - Loans - Allowance for Credit Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Balance	$ 12,292	$ 11,925
Charge-offs	(1,500)	(1,248)
Recoveries	1,439	1,615
Provision for loan and lease losses
Individually evaluated for impairment			$ 324	$ 1,237
Collectively evaluated for impairment			11,907	11,055
Total	12,292	11,925	12,231	12,292
Individually evaluated for impairment			10,399	11,012
Collectively evaluated for impairment			1,022,504	935,239
Total gross loans			1,032,903	946,251
Commercial Portfolio Segment [Member]
Balance	2,205	2,397
Charge-offs	(238)	(132)
Recoveries	927	865
Provision for loan and lease losses	(1,072)	(925)
Individually evaluated for impairment			159	748
Collectively evaluated for impairment			1,663	1,457
Total	2,205	2,397	1,822	2,205
Individually evaluated for impairment			656	2,183
Collectively evaluated for impairment			140,541	133,360
Total gross loans			141,197	135,543
Commercial Real Estate Portfolio Segment [Member]
Balance	7,116	6,514
Charge-offs	(233)
Recoveries
Provision for loan and lease losses	1,213	602
Individually evaluated for impairment				209
Collectively evaluated for impairment			8,096	6,907
Total	7,116	6,514	8,096	7,116
Individually evaluated for impairment			3,103	1,343
Collectively evaluated for impairment			736,480	659,550
Total gross loans			739,583	660,893
Residential Portfolio Segment [Member]
Balance	1,173	1,169
Charge-offs	(181)	(226)
Recoveries	261	435
Provision for loan and lease losses	(221)	(205)
Individually evaluated for impairment			154	273
Collectively evaluated for impairment			878	900
Total	1,173	1,169	1,032	1,173
Individually evaluated for impairment			6,600	7,463
Collectively evaluated for impairment			112,199	91,307
Total gross loans			118,799	98,770
Consumer Portfolio Segment [Member]
Balance	1,356	1,435
Charge-offs	(848)	(890)
Recoveries	251	315
Provision for loan and lease losses	174	496
Individually evaluated for impairment			11	7
Collectively evaluated for impairment			922	1,349
Total	1,356	1,435	933	1,356
Individually evaluated for impairment			40	23
Collectively evaluated for impairment			33,284	51,022
Total gross loans			33,324	51,045
Unallocated Financing Receivables [Member]
Balance	442	410
Charge-offs
Recoveries
Provision for loan and lease losses	(94)	32
Individually evaluated for impairment
Collectively evaluated for impairment			348	442
Total	$ 442	$ 410	348	442
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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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

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The balance of financing receivables that were collectively evaluated for impairment.

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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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