Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Balance	$ 7,390	$ 7,925	$ 8,300
Charge-offs	(920)	(689)	(819)
Recoveries	267	235	287
Provision for (recovery of) loan losses	126	(81)	157
Balance	6,863	7,390	7,925
Allowance for loan losses, individually evaluated for impairment				$ 110	$ 139
Allowance for loan losses, collectively evaluated for impairment				6,753	7,251
Allowance for loan losses	7,390	7,925	8,300	6,863	7,390
Loans, individually evaluated for impairment				5,289	6,820
Loans, collectively evaluated for impairment				728,738	703,577
Loans				734,027	710,397
Real Estate Construction Portfolio Segment[Member]
Balance	398	337	438
Charge-offs	0
Recoveries	0	0	0
Provision for (recovery of) loan losses	2	61	(101)
Balance	400	398	337
Allowance for loan losses, individually evaluated for impairment				0
Allowance for loan losses, collectively evaluated for impairment				400	398
Allowance for loan losses	400	337	438	400	398
Loans, individually evaluated for impairment				0
Loans, collectively evaluated for impairment				42,303	37,845
Loans				42,303	37,845
Consumer Real Estate Portfolio Segment [Member]
Balance	2,049	2,027	1,830
Charge-offs	(192)	(38)	(146)
Recoveries		3	1
Provision for (recovery of) loan losses	38	57	342
Balance	1,895	2,049	2,027
Allowance for loan losses, individually evaluated for impairment				2	4
Allowance for loan losses, collectively evaluated for impairment				1,893	2,045
Allowance for loan losses	1,895	2,027	1,830	1,895	2,049
Loans, individually evaluated for impairment				759	1,452
Loans, collectively evaluated for impairment				180,713	174,004
Loans				181,472	175,456
Commercial Real Estate Portfolio Segment [Member]
Balance	2,798	3,044	3,738
Charge-offs	(150)		(139)
Recoveries	49	49	131
Provision for (recovery of) loan losses	(138)	(295)	(686)
Balance	2,559	2,798	3,044
Allowance for loan losses, individually evaluated for impairment				0
Allowance for loan losses, collectively evaluated for impairment				2,559	2,798
Allowance for loan losses	2,559	3,044	3,738	2,559	2,798
Loans, individually evaluated for impairment				3,608	4,340
Loans, collectively evaluated for impairment				361,765	349,206
Loans				365,373	353,546
Commercial Non Real Estate Segment [Member]
Balance	602	1,072	1,063
Charge-offs	(47)	(107)	(82)
Recoveries	1	22	23
Provision for (recovery of) loan losses	(1)	(385)	68
Balance	555	602	1,072
Allowance for loan losses, individually evaluated for impairment				108	135
Allowance for loan losses, collectively evaluated for impairment				447	467
Allowance for loan losses	555	1,072	1,063	555	602
Loans, individually evaluated for impairment				918	1,015
Loans, collectively evaluated for impairment				45,658	45,520
Loans				46,576	46,535
Public Sector and IDA Portfolio Segment[Member]
Balance	583	419	330
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for (recovery of) loan losses	(105)	164	89
Balance	478	583	419
Allowance for loan losses, individually evaluated for impairment				0	0
Allowance for loan losses, collectively evaluated for impairment				478	583
Allowance for loan losses	478	419	330	478	583
Loans, individually evaluated for impairment				0	0
Loans, collectively evaluated for impairment				63,764	60,777
Loans				63,764	60,777
Consumer Non Real Estate Portfolio Segment [Member]
Balance	750	707	644
Charge-offs	(531)	(544)	(452)
Recoveries	217	161	132
Provision for (recovery of) loan losses	214	426	383
Balance	650	750	707
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment				650	750
Allowance for loan losses	650	707	644	650	750
Loans, individually evaluated for impairment				4	13
Loans, collectively evaluated for impairment				34,535	36,225
Loans				34,539	36,238
Unallocated Financing Receivables [Member]
Balance	210	319	257
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for (recovery of) loan losses	116	(109)	62
Balance	326	210	319
Allowance for loan losses, individually evaluated for impairment				0	0
Allowance for loan losses, collectively evaluated for impairment				326	210
Allowance for loan losses	$ 326	$ 319	$ 257	326	210
Loans, individually evaluated for impairment				0	0
Loans, collectively evaluated for impairment					0
Loans					$ 0

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually 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 allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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