Note 5 - Loans (Details) - Composition of Impaired Loans by Class (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	$ 20,426	$ 22,968
Impaired loans with no related allowance, unpaid principal balance	27,175	38,132
With an allowance recorded:
Impaired loans with related allowance, recorded investment	11,136	21,727
Impaired loans with related allowance, unpaid principal balance	12,971	23,027
Impaired loans, related allowance	1,737	2,555
Total:
Impaired loans, recorded investment	31,562	44,695
Impaired loans, unpaid principal balance	40,146	61,159
Impaired loans, related allowance	1,737	2,555
Construction, Land Development and Other Land Loan [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	283	3,244
Impaired loans with no related allowance, unpaid principal balance	805	6,503
With an allowance recorded:
Impaired loans with related allowance, recorded investment	6	260
Impaired loans with related allowance, unpaid principal balance	6	260
Impaired loans, related allowance		68
Total:
Impaired loans, recorded investment	289	3,504
Impaired loans, unpaid principal balance	811	6,763
Impaired loans, related allowance		68
Multi Family Residential [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment		181
Impaired loans with no related allowance, unpaid principal balance		239
Total:
Impaired loans, recorded investment		181
Impaired loans, unpaid principal balance		239
Non Farm Nonresidential [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	18,534	17,414
Impaired loans with no related allowance, unpaid principal balance	23,055	24,422
With an allowance recorded:
Impaired loans with related allowance, recorded investment	10,186	18,839
Impaired loans with related allowance, unpaid principal balance	12,021	18,839
Impaired loans, related allowance	1,555	1,668
Total:
Impaired loans, recorded investment	28,720	36,253
Impaired loans, unpaid principal balance	35,076	43,261
Impaired loans, related allowance	1,555	1,668
Commercial Real Estate Loans [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	18,817	20,839
Impaired loans with no related allowance, unpaid principal balance	23,860	31,164
With an allowance recorded:
Impaired loans with related allowance, recorded investment	10,192	19,099
Impaired loans with related allowance, unpaid principal balance	12,027	19,099
Impaired loans, related allowance	1,555	1,736
Total:
Impaired loans, recorded investment	29,009	39,938
Impaired loans, unpaid principal balance	35,887	50,263
Impaired loans, related allowance	1,555	1,736
Single-family Real Estate, Revolving, Open-end Loans [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	333
Impaired loans with no related allowance, unpaid principal balance	333
With an allowance recorded:
Impaired loans with related allowance, recorded investment		404
Impaired loans with related allowance, unpaid principal balance		404
Impaired loans, related allowance		83
Total:
Impaired loans, recorded investment	333	404
Impaired loans, unpaid principal balance	333	404
Impaired loans, related allowance		83
Single Family Residential Closed End First Lien [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	645	1,369
Impaired loans with no related allowance, unpaid principal balance	750	5,811
With an allowance recorded:
Impaired loans with related allowance, recorded investment	208	323
Impaired loans with related allowance, unpaid principal balance	208	323
Impaired loans, related allowance	24	18
Total:
Impaired loans, recorded investment	853	1,692
Impaired loans, unpaid principal balance	958	6,134
Impaired loans, related allowance	24	18
Single Family Residential Closed End Junior Lien [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	24
Impaired loans with no related allowance, unpaid principal balance	24
With an allowance recorded:
Impaired loans with related allowance, recorded investment	106	195
Impaired loans with related allowance, unpaid principal balance	106	195
Impaired loans, related allowance	41	62
Total:
Impaired loans, recorded investment	130	195
Impaired loans, unpaid principal balance	130	195
Impaired loans, related allowance	41	62
Single Family Residential [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	1,002	1,369
Impaired loans with no related allowance, unpaid principal balance	1,107	5,811
With an allowance recorded:
Impaired loans with related allowance, recorded investment	314	922
Impaired loans with related allowance, unpaid principal balance	314	922
Impaired loans, related allowance	65	163
Total:
Impaired loans, recorded investment	1,316	2,291
Impaired loans, unpaid principal balance	1,421	6,733
Impaired loans, related allowance	65	163
Commercial and Industrial [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment	607	753
Impaired loans with no related allowance, unpaid principal balance	2,208	1,150
With an allowance recorded:
Impaired loans with related allowance, recorded investment	616	1,680
Impaired loans with related allowance, unpaid principal balance	616	2,980
Impaired loans, related allowance	115	644
Total:
Impaired loans, recorded investment	1,223	2,433
Impaired loans, unpaid principal balance	2,824	4,130
Impaired loans, related allowance	115	644
Consumer [Member]
With no related allowance recorded:
Impaired loans with no related allowance, recorded investment		7
Impaired loans with no related allowance, unpaid principal balance		7
With an allowance recorded:
Impaired loans with related allowance, recorded investment	14	26
Impaired loans with related allowance, unpaid principal balance	14	26
Impaired loans, related allowance	2	12
Total:
Impaired loans, recorded investment	14	33
Impaired loans, unpaid principal balance	14	33
Impaired loans, related allowance	$ 2	$ 12

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

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