Note 5 - Loans and Related Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Individually evaluated for impairment			$ 660	$ 1,354
Collectively evaluated for impairment			6,108	6,074
Less allowance for loan and lease losses	$ 7,428	$ 7,190	6,768	7,428
ALLL balance, period start	7,428	7,190
Charge-offs	(1,809)	(1,118)
Recoveries	259	516
Provision	890	840
ALLL balance, period end	6,768	7,428
Commercial And Industrial [Member]
Individually evaluated for impairment			3	667
Collectively evaluated for impairment			453	302
Less allowance for loan and lease losses	969	999	456	969
ALLL balance, period start	969	999
Charge-offs	(519)	(610)
Recoveries	82	287
Provision	(76)	293
ALLL balance, period end	456	969
Real Estate Construction Porfolio Segment [Member]
Individually evaluated for impairment
Collectively evaluated for impairment			97	100
Less allowance for loan and lease losses	100	313	97	100
ALLL balance, period start	100	313
Charge-offs
Recoveries	74	63
Provision	(77)	(276)
ALLL balance, period end	97	100
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Individually evaluated for impairment			30	43
Collectively evaluated for impairment			1,628	1,538
Less allowance for loan and lease losses	1,581	1,760	1,658	1,581
ALLL balance, period start	1,581	1,760
Charge-offs	(523)	(177)
Recoveries	78	128
Provision	522	(130)
ALLL balance, period end	1,658	1,581
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Individually evaluated for impairment			627	643
Collectively evaluated for impairment			3,902	4,008
Less allowance for loan and lease losses	4,651	4,036	4,529	4,651
ALLL balance, period start	4,651	4,036
Charge-offs	(32)	(111)
Recoveries	17
Provision	(107)	726
ALLL balance, period end	4,529	4,651
Consumer Portfolio Segment [Member]
Individually evaluated for impairment				1
Collectively evaluated for impairment			28	126
Less allowance for loan and lease losses	127	82	$ 28	$ 127
ALLL balance, period start	127	82
Charge-offs	(735)	(220)
Recoveries	8	38
Provision	628	227
ALLL balance, period end	$ 28	$ 127

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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

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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.

+ References

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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