Note 4 - Loans Held for Investment - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Recorded investment with no allowance recorded	$ 9,924	$ 14,183
Contractual unpaid principal balance with no allowance recorded	10,140	14,539
YTD average recorded investment with no allowance recorded	11,414	15,608
Interest income recognized on impaired loans with no allowance recorded	589	796
Recorded investment with an allowance recorded	1,199	1,637
Contractual unpaid principal balance with an allowance recorded	1,637	1,639
Related allowance	393	618
YTD average recorded investment with an allowance recorded	1,332	2,214
Interest income recognized on impaired loans with an allowance recorded	87	96
Total, recorded investment	11,123	15,820
Total, contractual unpaid principal balance	11,777	16,178
Total, YTD average recorded investment	12,746	17,822
Total, interest income recognized on impaired loans	676	892
Residential Portfolio Segment [Member]
Related allowance
Total, recorded investment	597	1,087
Total, contractual unpaid principal balance	730	1,384
Total, YTD average recorded investment	804	1,180
Total, interest income recognized on impaired loans	32	62
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment with no allowance recorded	597	1,087
Contractual unpaid principal balance with no allowance recorded	730	1,384
YTD average recorded investment with no allowance recorded	804	1,180
Interest income recognized on impaired loans with no allowance recorded	32	62
Commercial Portfolio Segment [Member]
Related allowance	226	379
Total, recorded investment	9,397	13,588
Total, contractual unpaid principal balance	9,897	13,642
Total, YTD average recorded investment	10,804	15,491
Total, interest income recognized on impaired loans	584	778
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment with no allowance recorded	6,581	9,521
Contractual unpaid principal balance with no allowance recorded	6,645	9,573
YTD average recorded investment with no allowance recorded	7,742	10,883
Interest income recognized on impaired loans with no allowance recorded	408	564
Recorded investment with an allowance recorded	287	821
Contractual unpaid principal balance with an allowance recorded	287	823
Related allowance		365
YTD average recorded investment with an allowance recorded	579	1,434
Interest income recognized on impaired loans with an allowance recorded	15	57
Commercial Portfolio Segment [Member] \| Lots and Raw Land [Member]
Recorded investment with no allowance recorded	2,185	2,616
Contractual unpaid principal balance with no allowance recorded	2,185	2,616
YTD average recorded investment with no allowance recorded	2,376	2,764
Interest income recognized on impaired loans with no allowance recorded	121	139
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment with no allowance recorded		574
Contractual unpaid principal balance with no allowance recorded		574
YTD average recorded investment with no allowance recorded		305
Interest income recognized on impaired loans with no allowance recorded		14
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Recorded investment with no allowance recorded	102	42
Contractual unpaid principal balance with no allowance recorded	102	42
YTD average recorded investment with no allowance recorded	59	44
Interest income recognized on impaired loans with no allowance recorded	5	2
Recorded investment with an allowance recorded	242	14
Contractual unpaid principal balance with an allowance recorded	678	14
Related allowance	226	14
YTD average recorded investment with an allowance recorded	48	61
Interest income recognized on impaired loans with an allowance recorded	35	2
Consumer Portfolio Segment [Member]
Related allowance	167	239
Total, recorded investment	1,129	1,145
Total, contractual unpaid principal balance	1,150	1,152
Total, YTD average recorded investment	1,138	1,151
Total, interest income recognized on impaired loans	60	52
Consumer Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment with no allowance recorded	221	201
Contractual unpaid principal balance with no allowance recorded	232	207
YTD average recorded investment with no allowance recorded	257	277
Interest income recognized on impaired loans with no allowance recorded	8	8
Recorded investment with an allowance recorded		79
Contractual unpaid principal balance with an allowance recorded		79
Related allowance		30
YTD average recorded investment with an allowance recorded		100
Interest income recognized on impaired loans with an allowance recorded		2
Consumer Portfolio Segment [Member] \| Lots and Raw Land [Member]
Recorded investment with no allowance recorded	129	50
Contractual unpaid principal balance with no allowance recorded	135	50
YTD average recorded investment with no allowance recorded	86	55
Interest income recognized on impaired loans with no allowance recorded	10	3
Recorded investment with an allowance recorded	647	723
Contractual unpaid principal balance with an allowance recorded	647	723
Related allowance	144	209
YTD average recorded investment with an allowance recorded	687	619
Interest income recognized on impaired loans with an allowance recorded	34	35
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment with no allowance recorded	71	50
Contractual unpaid principal balance with no allowance recorded	73	51
YTD average recorded investment with no allowance recorded	50	56
Interest income recognized on impaired loans with no allowance recorded	3	2
Recorded investment with an allowance recorded	23
Contractual unpaid principal balance with an allowance recorded	25
Related allowance	23
YTD average recorded investment with an allowance recorded	18
Interest income recognized on impaired loans with an allowance recorded	3
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Recorded investment with no allowance recorded	38	42
Contractual unpaid principal balance with no allowance recorded	38	42
YTD average recorded investment with no allowance recorded	40	44
Interest income recognized on impaired loans with no allowance recorded	$ 2	$ 2

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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