Note 5 - Loans - Loans Individually Evaluated for Impairment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Loans with no related allowance recorded, recorded investment	$ 3,609	$ 6,151
Loans with no related allowance recorded, unpaid principal balance	4,392	8,012
Loans with no related allowance recorded, average recorded investment	4,996	4,005
Loans with an allowance recorded, recorded investment	2,660	2,602
Loans with an allowance recorded, unpaid principal balance	3,135	4,173
Related allowance	1,267	544
Loans with an allowance recorded, average recorded investment	2,567	6,598
Recorded investment	6,269	8,753
Unpaid principal balance	7,527	12,185
Average recorded investment	7,563	10,603
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	3,609	6,151
Loans with no related allowance recorded, unpaid principal balance	4,392	8,012
Loans with no related allowance recorded, average recorded investment	4,996	4,005
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	2,660	2,602
Loans with an allowance recorded, unpaid principal balance	3,135	4,173
Related allowance	1,267	544
Loans with an allowance recorded, average recorded investment	2,567	6,598
Total:
Recorded investment	6,269	8,753
Unpaid principal balance	7,527	12,185
Related allowance	1,267	544
Average recorded investment	7,563	10,603
Commercial and Industrial Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	322	3,119
Loans with no related allowance recorded, unpaid principal balance	465	3,859
Loans with no related allowance recorded, average recorded investment	1,947	1,414
Loans with an allowance recorded, recorded investment	2,360	1,516
Loans with an allowance recorded, unpaid principal balance	2,835	3,087
Related allowance	1,207	268
Loans with an allowance recorded, average recorded investment	1,619	4,612
Recorded investment	2,682	4,635
Unpaid principal balance	3,300	6,946
Average recorded investment	3,566	6,026
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	322	3,119
Loans with no related allowance recorded, unpaid principal balance	465	3,859
Loans with no related allowance recorded, average recorded investment	1,947	1,414
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	2,360	1,516
Loans with an allowance recorded, unpaid principal balance	2,835	3,087
Related allowance	1,207	268
Loans with an allowance recorded, average recorded investment	1,619	4,612
Total:
Recorded investment	2,682	4,635
Unpaid principal balance	3,300	6,946
Related allowance	1,207	268
Average recorded investment	3,566	6,026
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	538
Loans with no related allowance recorded, unpaid principal balance	708	151
Loans with no related allowance recorded, average recorded investment	108	21
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment	182	368
Recorded investment	538
Unpaid principal balance	708	151
Average recorded investment	290	389
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	538
Loans with no related allowance recorded, unpaid principal balance	708	151
Loans with no related allowance recorded, average recorded investment	108	21
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment	182	368
Total:
Recorded investment	538
Unpaid principal balance	708	151
Related allowance
Average recorded investment	290	389
Undevelopment Land Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	233
Loans with no related allowance recorded, unpaid principal balance	265
Loans with no related allowance recorded, average recorded investment	76
Loans with an allowance recorded, recorded investment	241
Loans with an allowance recorded, unpaid principal balance	241
Related allowance	1
Loans with an allowance recorded, average recorded investment	149
Recorded investment	474
Unpaid principal balance	506
Average recorded investment	225
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	233
Loans with no related allowance recorded, unpaid principal balance	265
Loans with no related allowance recorded, average recorded investment	76
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	241
Loans with an allowance recorded, unpaid principal balance	241
Related allowance	1
Loans with an allowance recorded, average recorded investment	149
Total:
Recorded investment	474
Unpaid principal balance	506
Related allowance	1
Average recorded investment	225
Real Estate Mortgage Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	2,516	3,032
Loans with no related allowance recorded, unpaid principal balance	2,954	4,002
Loans with no related allowance recorded, average recorded investment	2,847	2,567
Loans with an allowance recorded, recorded investment		1,018
Loans with an allowance recorded, unpaid principal balance		1,018
Related allowance		208
Loans with an allowance recorded, average recorded investment	554	1,546
Recorded investment	2,516	4,050
Unpaid principal balance	2,954	5,020
Average recorded investment	3,401	4,113
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	2,516	3,032
Loans with no related allowance recorded, unpaid principal balance	2,954	4,002
Loans with no related allowance recorded, average recorded investment	2,847	2,567
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment		1,018
Loans with an allowance recorded, unpaid principal balance		1,018
Related allowance		208
Loans with an allowance recorded, average recorded investment	554	1,546
Total:
Recorded investment	2,516	4,050
Unpaid principal balance	2,954	5,020
Related allowance		208
Average recorded investment	3,401	4,113
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans with no related allowance recorded, recorded investment	107	278
Loans with no related allowance recorded, unpaid principal balance	107	278
Loans with no related allowance recorded, average recorded investment	193	178
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		92
Recorded investment	107	278
Unpaid principal balance	107	278
Average recorded investment	193	270
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	107	278
Loans with no related allowance recorded, unpaid principal balance	107	278
Loans with no related allowance recorded, average recorded investment	193	178
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		92
Total:
Recorded investment	107	278
Unpaid principal balance	107	278
Related allowance
Average recorded investment	193	270
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans with no related allowance recorded, recorded investment	1,042	1,743
Loans with no related allowance recorded, unpaid principal balance	1,479	2,713
Loans with no related allowance recorded, average recorded investment	1,356	1,622
Loans with an allowance recorded, recorded investment		1,018
Loans with an allowance recorded, unpaid principal balance		1,018
Related allowance		208
Loans with an allowance recorded, average recorded investment	554	1,266
Recorded investment	1,042	2,761
Unpaid principal balance	1,479	3,731
Average recorded investment	1,910	2,888
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	1,042	1,743
Loans with no related allowance recorded, unpaid principal balance	1,479	2,713
Loans with no related allowance recorded, average recorded investment	1,356	1,622
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment		1,018
Loans with an allowance recorded, unpaid principal balance		1,018
Related allowance		208
Loans with an allowance recorded, average recorded investment	554	1,266
Total:
Recorded investment	1,042	2,761
Unpaid principal balance	1,479	3,731
Related allowance		208
Average recorded investment	1,910	2,888
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans with no related allowance recorded, recorded investment	984	906
Loans with no related allowance recorded, unpaid principal balance	985	906
Loans with no related allowance recorded, average recorded investment	980	661
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		188
Recorded investment	984	906
Unpaid principal balance	985	906
Average recorded investment	980	849
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	984	906
Loans with no related allowance recorded, unpaid principal balance	985	906
Loans with no related allowance recorded, average recorded investment	980	661
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		188
Total:
Recorded investment	984	906
Unpaid principal balance	985	906
Related allowance
Average recorded investment	980	849
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans with no related allowance recorded, recorded investment		13
Loans with no related allowance recorded, unpaid principal balance		13
Loans with no related allowance recorded, average recorded investment	3	37
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Recorded investment		13
Unpaid principal balance		13
Average recorded investment	3	37
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment		13
Loans with no related allowance recorded, unpaid principal balance		13
Loans with no related allowance recorded, average recorded investment	3	37
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Total:
Recorded investment		13
Unpaid principal balance		13
Related allowance
Average recorded investment	3	37
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans with no related allowance recorded, recorded investment	383	92
Loans with no related allowance recorded, unpaid principal balance	383	92
Loans with no related allowance recorded, average recorded investment	315	69
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Recorded investment	383	92
Unpaid principal balance	383	92
Average recorded investment	315	69
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	383	92
Loans with no related allowance recorded, unpaid principal balance	383	92
Loans with no related allowance recorded, average recorded investment	315	69
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Total:
Recorded investment	383	92
Unpaid principal balance	383	92
Related allowance
Average recorded investment	315	69
Consumer Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment
Loans with no related allowance recorded, unpaid principal balance
Loans with no related allowance recorded, average recorded investment	18	3
Loans with an allowance recorded, recorded investment	59	68
Loans with an allowance recorded, unpaid principal balance	59	68
Related allowance	59	68
Loans with an allowance recorded, average recorded investment	63	72
Recorded investment	59	68
Unpaid principal balance	59	68
Average recorded investment	81	75
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment
Loans with no related allowance recorded, unpaid principal balance
Loans with no related allowance recorded, average recorded investment	18	3
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	59	68
Loans with an allowance recorded, unpaid principal balance	59	68
Related allowance	59	68
Loans with an allowance recorded, average recorded investment	63	72
Total:
Recorded investment	59	68
Unpaid principal balance	59	68
Related allowance	59	68
Average recorded investment	$ 81	$ 75