Note 7 - Loans and Related Allowance of Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Dec. 31, 2016
Individually evaluated for impairment					$ 1,260,000	$ 527,000
Collectively evaluated for impairment					5,592,000	6,071,000
Total ending allowance balance	$ 6,852,000	$ 6,334,000	$ 6,852,000	$ 6,385,000	6,852,000	6,598,000
ALLL balance, period start	6,605,000	6,366,000	6,598,000	6,385,000
Charge-offs	(253,000)	(226,000)	(936,000)	(679,000)
Recoveries	220,000	89,000	575,000	313,000
Provision for Loan, Lease, and Other Losses	280,000	105,000	615,000	315,000
ALLL balance, period end	6,852,000	6,334,000	6,852,000	6,334,000
Commercial And Industrial [Member]
Individually evaluated for impairment					436,000	90,000
Collectively evaluated for impairment					291,000	358,000
Total ending allowance balance	727,000	513,000	727,000	867,000	727,000	448,000
ALLL balance, period start	613,000	484,000	448,000	867,000
Charge-offs	(4,000)	(74,000)	(439,000)	(197,000)
Recoveries	46,000	4,000	189,000	51,000
Provision for Loan, Lease, and Other Losses	72,000	99,000	529,000	(208,000)
ALLL balance, period end	727,000	513,000	727,000	513,000
Real Estate Construction Porfolio Segment [Member]
Individually evaluated for impairment
Collectively evaluated for impairment					259,000	172,000
Total ending allowance balance	259,000	138,000	259,000	276,000	259,000	172,000
ALLL balance, period start	202,000	159,000	172,000	276,000
Charge-offs
Recoveries	11,000		34,000
Provision for Loan, Lease, and Other Losses	46,000	(21,000)	53,000	(138,000)
ALLL balance, period end	259,000	138,000	259,000	138,000
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Individually evaluated for impairment					132,000	251,000
Collectively evaluated for impairment					1,704,000	2,567,000
Total ending allowance balance	1,836,000	2,761,000	1,836,000	3,139,000	1,836,000	2,818,000
ALLL balance, period start	1,767,000	2,788,000	2,818,000	3,139,000
Charge-offs		(149,000)	(74,000)	(394,000)
Recoveries	45,000	82,000	59,000	113,000
Provision for Loan, Lease, and Other Losses	24,000	40,000	(967,000)	(97,000)
ALLL balance, period end	1,836,000	2,761,000	1,836,000	2,761,000
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Individually evaluated for impairment					692,000	186,000
Collectively evaluated for impairment					2,991,000	2,949,000
Total ending allowance balance	3,683,000	2,895,000	3,683,000	2,078,000	3,683,000	3,135,000
ALLL balance, period start	4,012,000	2,909,000	3,135,000	2,078,000
Charge-offs	(20,000)		(39,000)	(70,000)
Recoveries	111,000		111,000	140,000
Provision for Loan, Lease, and Other Losses	(420,000)	(14,000)	476,000	747,000
ALLL balance, period end	3,683,000	2,895,000	3,683,000	2,895,000
Consumer Portfolio Segment [Member]
Individually evaluated for impairment
Collectively evaluated for impairment					347,000	25,000
Total ending allowance balance	347,000	27,000	347,000	25,000	$ 347,000	$ 25,000
ALLL balance, period start	11,000	26,000	25,000	25,000
Charge-offs	(229,000)	(3,000)	(384,000)	(18,000)
Recoveries	7,000	3,000	182,000	9,000
Provision for Loan, Lease, and Other Losses	558,000	1,000	524,000	11,000
ALLL balance, period end	$ 347,000	$ 27,000	$ 347,000	$ 27,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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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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