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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Past Due and Nonaccrual Loans (Details) - USD ($)		Sep. 30, 2016		Dec. 31, 2015	Sep. 30, 2015
Financing Receivables 30 to 89 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member]
Past due loans		$ 0	[1]	$ 0
Financing Receivables 30 to 89 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Other [Member]
Past due loans				26,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member]
Past due loans		37,000	[1]	16,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member]
Past due loans		801,000	[1]	1,402,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member]
Past due loans		117,000	[1]	123,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member]
Past due loans		239,000	[1]	248,000
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member]
Past due loans		318,000	[1]	684,000
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member]
Past due loans		127,000	[1]	0
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Past due loans		0	[1]	0
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member]
Past due loans	[1]	66,000
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Past due loans				142,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member]
Past due loans		3,000	[1]	5,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member]
Past due loans		225,000	[1]	286,000
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member]
Past due loans		74,000	[1]	60,000
Financing Receivables 30 to 89 Days Past Due [Member] | Public Sector and IDA Portfolio Segment[Member]
Past due loans				0
Financing Receivables 30 to 89 Days Past Due [Member]
Past due loans		2,007,000	[1]	2,992,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member]
Past due loans		0	[1]	0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Other [Member]
Past due loans				0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member]
Past due loans		0	[1]	0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member]
Past due loans		181,000	[1]	106,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member]
Past due loans		37,000	[1]	39,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member]
Past due loans		0	[1]	0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member]
Past due loans		1,459,000	[1]	1,728,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member]
Past due loans		455,000	[1]	357,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Past due loans		0	[1]	0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member]
Past due loans	[1]	335,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Past due loans				883,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member]
Past due loans		11,000	[1]	6,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member]
Past due loans		6,000	[1]	5,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member]
Past due loans		4,000	[1]	0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Public Sector and IDA Portfolio Segment[Member]
Past due loans				0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans		2,488,000	[1]	3,124,000
Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member]
Loans past due 90 days or more and still accruing		0	[1]	0
Nonaccruals (including impaired nonaccruals)		273,000	[1]	718,000
Real Estate Construction Portfolio Segment[Member] | Construction Other [Member]
Loans past due 90 days or more and still accruing				0
Nonaccruals (including impaired nonaccruals)				0
Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member]
Loans past due 90 days or more and still accruing		0	[1]	0
Nonaccruals (including impaired nonaccruals)		0	[1]	0
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member]
Loans past due 90 days or more and still accruing		137,000	[1]	106,000
Nonaccruals (including impaired nonaccruals)		44,000	[1]	14,000
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member]
Loans past due 90 days or more and still accruing		37,000	[1]	39,000
Nonaccruals (including impaired nonaccruals)		0	[1]	0
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member]
Loans past due 90 days or more and still accruing		0	[1]	0
Nonaccruals (including impaired nonaccruals)		19,000	[1]	0
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member]
Loans past due 90 days or more and still accruing		0	[1]	0
Nonaccruals (including impaired nonaccruals)		1,459,000	[1]	1,728,000
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member]
Loans past due 90 days or more and still accruing		0	[1]	0
Nonaccruals (including impaired nonaccruals)		574,000	[1]	494,000
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans past due 90 days or more and still accruing		0	[1]	0
Nonaccruals (including impaired nonaccruals)		2,760,000	[1]	2,845,000
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member]
Loans past due 90 days or more and still accruing	[1]	0
Nonaccruals (including impaired nonaccruals)	[1]	361,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans past due 90 days or more and still accruing				0
Nonaccruals (including impaired nonaccruals)				883,000
Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member]
Loans past due 90 days or more and still accruing		11,000	[1]	6,000
Nonaccruals (including impaired nonaccruals)		0	[1]	0
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member]
Loans past due 90 days or more and still accruing		6,000	[1]	5,000
Nonaccruals (including impaired nonaccruals)		3,000	[1]	0
Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member]
Loans past due 90 days or more and still accruing		4,000	[1]	0
Nonaccruals (including impaired nonaccruals)		0	[1]	0
Public Sector and IDA Portfolio Segment[Member]
Loans past due 90 days or more and still accruing				0
Nonaccruals (including impaired nonaccruals)				0
Loans past due 90 days or more and still accruing		195,000	[1]	156,000	$ 47,000
Nonaccruals (including impaired nonaccruals)		$ 5,493,000	[1]	$ 6,682,000	$ 8,988,000
[1] Only classes with past-due or nonaccrual loans are shown.

X

- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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