Note 6 - Loans Receivable and Allowances for Loan Losses - Impaired Loans Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Commercial Real Estate Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	$ 12,188	$ 13,923	$ 11,954	$ 13,073
With no related allowance recorded - Interest income recognized	65	73	197	214
With related allowance recorded - Average recorded investment	6,058	2,479	3,844	6,803
With related allowance recorded - Interest income recognized	19	3	43	6
Average recorded investment	18,246	16,402	15,798	19,876
Interest income recognized	84	76	240	220
Construction and Land Development Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	22	328	72	228
With no related allowance recorded - Interest income recognized		2		3
With related allowance recorded - Average recorded investment	43	62	15	112
With related allowance recorded - Interest income recognized
Average recorded investment	65	390	87	340
Interest income recognized		2		3
Commercial Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	1,611	2,459	1,797	3,435
With no related allowance recorded - Interest income recognized	9	16	30	64
With related allowance recorded - Average recorded investment	3,607	3,776	3,389	2,456
With related allowance recorded - Interest income recognized	18	12	56	12
Average recorded investment	5,218	6,235	5,186	5,891
Interest income recognized	27	28	86	76
Owner Occupied Real Estate [Member]
With no related allowance recorded - Average recorded investment	665	589	647	749
With no related allowance recorded - Interest income recognized	3	1	6	5
With related allowance recorded - Average recorded investment	1,977	3,293	2,205	3,837
With related allowance recorded - Interest income recognized	9	27	23	90
Average recorded investment	2,642	3,882	2,852	4,586
Interest income recognized	12	28	29	95
Consumer Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	1,027	754	901	656
With no related allowance recorded - Interest income recognized	5	3	11	7
With related allowance recorded - Average recorded investment	278	111	252	37
With related allowance recorded - Interest income recognized	2	1	7	1
Average recorded investment	1,305	865	1,153	693
Interest income recognized	7	4	18	8
With no related allowance recorded - Average recorded investment	15,513	18,053	15,371	18,141
With no related allowance recorded - Interest income recognized	82	95	244	293
With related allowance recorded - Average recorded investment	11,963	9,721	9,705	13,245
With related allowance recorded - Interest income recognized	48	43	129	109
Average recorded investment	27,476	27,774	25,076	31,386
Interest income recognized	$ 130	$ 138	$ 373	$ 402

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

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=66008989&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
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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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
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

Reference 2: 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=66008989&loc=d3e5212-111524

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