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Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	$ 4,352,000		$ 3,499,000
With no related allowance recorded, principal balance	3,297,000		2,467,000
With no related allowance recorded, average recorded principal balance	2,883,000	$ 8,282,000
With related allowance recorded, unpaid principal balance	10,996,000		11,008,000
With related allowance recorded, principal balance	10,910,000		10,916,000
Related allowance	3,581,000		1,572,000
With related allowance recorded, average recorded principal balance	10,913,000	9,683,000
Total unpaid principal balance	15,348,000		14,507,000
Total principal balance	14,207,000		13,383,000
Total average recorded principal balance	13,796,000	17,965,000
Originated Loan [Member] | Commercial Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance	2,650,000		2,115,000
With no related allowance recorded, principal balance	2,249,000		1,723,000
With no related allowance recorded, average recorded principal balance	1,987,000	7,660,000
With related allowance recorded, unpaid principal balance	9,834,000		10,370,000
With related allowance recorded, principal balance	9,811,000		10,347,000
Related allowance	2,846,000		1,303,000
With related allowance recorded, average recorded principal balance	10,079,000	9,040,000
Total unpaid principal balance	12,484,000		12,485,000
Total principal balance	12,060,000		12,070,000
Total average recorded principal balance	12,066,000	16,700,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
With no related allowance recorded, unpaid principal balance	1,680,000		1,498,000
With no related allowance recorded, principal balance	1,680,000		1,498,000
With no related allowance recorded, average recorded principal balance	1,589,000	1,695,000
With related allowance recorded, unpaid principal balance	3,021,000		2,405,000
With related allowance recorded, principal balance	2,998,000		2,382,000
Related allowance	2,368,000		673,000
With related allowance recorded, average recorded principal balance	2,690,000	270,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
With no related allowance recorded, unpaid principal balance	479,000		487,000
With no related allowance recorded, principal balance	80,000		95,000
With no related allowance recorded, average recorded principal balance	88,000	0
With related allowance recorded, unpaid principal balance	499,000		999,000
With related allowance recorded, principal balance	499,000		999,000
Related allowance	13,000		28,000
With related allowance recorded, average recorded principal balance	749,000	1,648,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance	227,000		0
With no related allowance recorded, principal balance	225,000		0
With no related allowance recorded, average recorded principal balance	113,000	287,000
With related allowance recorded, unpaid principal balance	1,382,000		906,000
With related allowance recorded, principal balance	1,382,000		906,000
Related allowance	209,000		97,000
With related allowance recorded, average recorded principal balance	1,144,000	1,307,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance	0		0
With no related allowance recorded, principal balance	0		0
With no related allowance recorded, average recorded principal balance	0	5,678,000
With related allowance recorded, unpaid principal balance	4,470,000		5,020,000
With related allowance recorded, principal balance	4,470,000		5,020,000
Related allowance	157,000		247,000
With related allowance recorded, average recorded principal balance	4,745,000	4,798,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
With no related allowance recorded, unpaid principal balance	264,000		130,000
With no related allowance recorded, principal balance	264,000		130,000
With no related allowance recorded, average recorded principal balance	197,000	0
With related allowance recorded, unpaid principal balance	462,000		1,040,000
With related allowance recorded, principal balance	462,000		1,040,000
Related allowance	99,000		258,000
With related allowance recorded, average recorded principal balance	751,000	1,017,000
Originated Loan [Member] | Retail Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance	1,702,000		1,384,000
With no related allowance recorded, principal balance	1,048,000		744,000
With no related allowance recorded, average recorded principal balance	896,000	622,000
With related allowance recorded, unpaid principal balance	1,162,000		638,000
With related allowance recorded, principal balance	1,099,000		569,000
Related allowance	735,000		269,000
With related allowance recorded, average recorded principal balance	834,000	643,000
Total unpaid principal balance	2,864,000		2,022,000
Total principal balance	2,147,000		1,313,000
Total average recorded principal balance	1,730,000	1,265,000
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
With no related allowance recorded, unpaid principal balance	386,000		114,000
With no related allowance recorded, principal balance	380,000		114,000
With no related allowance recorded, average recorded principal balance	247,000	7,000
With related allowance recorded, unpaid principal balance	997,000		434,000
With related allowance recorded, principal balance	982,000		412,000
Related allowance	715,000		203,000
With related allowance recorded, average recorded principal balance	697,000	516,000
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
With no related allowance recorded, unpaid principal balance	1,316,000		1,270,000
With no related allowance recorded, principal balance	668,000		630,000
With no related allowance recorded, average recorded principal balance	649,000	615,000
With related allowance recorded, unpaid principal balance	165,000		204,000
With related allowance recorded, principal balance	117,000		157,000
Related allowance	20,000		66,000
With related allowance recorded, average recorded principal balance	137,000	127,000
Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	5,954,000		5,826,000
With no related allowance recorded, principal balance	5,011,000		4,894,000
With no related allowance recorded, average recorded principal balance	4,952,000	6,146,000
With related allowance recorded, unpaid principal balance	239,000		239,000
With related allowance recorded, principal balance	239,000		239,000
Related allowance	9,000		9,000
With related allowance recorded, average recorded principal balance	239,000	538,000
Total unpaid principal balance	6,193,000		6,065,000
Total principal balance	5,250,000		5,133,000
Total average recorded principal balance	5,191,000	6,684,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance	3,310,000		3,214,000
With no related allowance recorded, principal balance	2,994,000		2,914,000
With no related allowance recorded, average recorded principal balance	2,954,000	4,442,000
With related allowance recorded, unpaid principal balance	67,000		67,000
With related allowance recorded, principal balance	67,000		67,000
Related allowance	5,000		5,000
With related allowance recorded, average recorded principal balance	67,000	450,000
Total unpaid principal balance	3,377,000		3,281,000
Total principal balance	3,061,000		2,981,000
Total average recorded principal balance	3,021,000	4,892,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
With no related allowance recorded, unpaid principal balance	985,000		853,000
With no related allowance recorded, principal balance	958,000		826,000
With no related allowance recorded, average recorded principal balance	892,000	1,462,000
With related allowance recorded, unpaid principal balance	19,000		19,000
With related allowance recorded, principal balance	19,000		19,000
Related allowance	2,000		2,000
With related allowance recorded, average recorded principal balance	19,000	378,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
With no related allowance recorded, unpaid principal balance	0		0
With no related allowance recorded, principal balance	0		0
With no related allowance recorded, average recorded principal balance	0	0
With related allowance recorded, unpaid principal balance	0		0
With related allowance recorded, principal balance	0		0
Related allowance	0		0
With related allowance recorded, average recorded principal balance	0	0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance	1,159,000		1,281,000
With no related allowance recorded, principal balance	1,092,000		1,210,000
With no related allowance recorded, average recorded principal balance	1,151,000	1,811,000
With related allowance recorded, unpaid principal balance	48,000		48,000
With related allowance recorded, principal balance	48,000		48,000
Related allowance	3,000		3,000
With related allowance recorded, average recorded principal balance	48,000	50,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance	848,000		928,000
With no related allowance recorded, principal balance	713,000		789,000
With no related allowance recorded, average recorded principal balance	751,000	826,000
With related allowance recorded, unpaid principal balance	0		0
With related allowance recorded, principal balance	0		0
Related allowance	0		0
With related allowance recorded, average recorded principal balance	0	0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
With no related allowance recorded, unpaid principal balance	318,000		152,000
With no related allowance recorded, principal balance	231,000		89,000
With no related allowance recorded, average recorded principal balance	160,000	343,000
With related allowance recorded, unpaid principal balance	0		0
With related allowance recorded, principal balance	0		0
Related allowance	0		0
With related allowance recorded, average recorded principal balance	0	22,000
Acquired Loan [Member] | Retail Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance	2,644,000		2,612,000
With no related allowance recorded, principal balance	2,017,000		1,980,000
With no related allowance recorded, average recorded principal balance	1,998,000	1,704,000
With related allowance recorded, unpaid principal balance	172,000		172,000
With related allowance recorded, principal balance	172,000		172,000
Related allowance	4,000		4,000
With related allowance recorded, average recorded principal balance	172,000	88,000
Total unpaid principal balance	2,816,000		2,784,000
Total principal balance	2,189,000		2,152,000
Total average recorded principal balance	2,170,000	1,792,000
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
With no related allowance recorded, unpaid principal balance	476,000		531,000
With no related allowance recorded, principal balance	322,000		351,000
With no related allowance recorded, average recorded principal balance	336,000	293,000
With related allowance recorded, unpaid principal balance	0		0
With related allowance recorded, principal balance	0		0
Related allowance	0		0
With related allowance recorded, average recorded principal balance	0	0
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
With no related allowance recorded, unpaid principal balance	2,168,000		2,081,000
With no related allowance recorded, principal balance	1,695,000		1,629,000
With no related allowance recorded, average recorded principal balance	1,662,000	1,411,000
With related allowance recorded, unpaid principal balance	172,000		172,000
With related allowance recorded, principal balance	172,000		172,000
Related allowance	4,000		$ 4,000
With related allowance recorded, average recorded principal balance	$ 172,000	$ 88,000

X

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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