Note 6 - Loans (Details) - Impaired Loans by Loan Class (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	$ 20,227	$ 21,500
Unpaid principle balance with no related allowance recorded	29,320	32,353
Recorded investment with an allowance recorded	7,508	9,908
Unpaid principle balance with an allowance recorded	8,290	10,635
Related allowance	1,532	1,556
Subtotal:
Recorded investment	27,735	31,408
Unpaid principle balance	37,610	42,988
Related allowance	1,532	1,556
Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	3,917	4,298
Unpaid principle balance with no related allowance recorded	8,134	8,461
Recorded investment with an allowance recorded	996	2,299
Unpaid principle balance with an allowance recorded	1,023	2,317
Related allowance	247	314
Subtotal:
Recorded investment	4,913	6,597
Unpaid principle balance	9,157	10,778
Related allowance	247	314
Commercial Real Estate Other Receivable [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	7,666	8,287
Unpaid principle balance with no related allowance recorded	9,916	12,309
Recorded investment with an allowance recorded	2,563	3,466
Unpaid principle balance with an allowance recorded	3,211	4,064
Related allowance	415	432
Subtotal:
Related allowance	415	432
Residential One to Four Family [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	8,443	8,714
Unpaid principle balance with no related allowance recorded	11,068	11,381
Recorded investment with an allowance recorded	3,341	3,529
Unpaid principle balance with an allowance recorded	3,448	3,640
Related allowance	569	506
Subtotal:
Related allowance	569	506
Residential Real Estate and Home Equities [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	201	201
Unpaid principle balance with no related allowance recorded	202	202
Recorded investment with an allowance recorded	574	579
Unpaid principle balance with an allowance recorded	574	579
Related allowance	287	289
Subtotal:
Related allowance	287	289
Consumer Other Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with an allowance recorded	34	35
Unpaid principle balance with an allowance recorded	34	35
Related allowance	14	15
Subtotal:
Recorded investment	34	35
Unpaid principle balance	34	35
Related allowance	14	15
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Related allowance	415	432
Subtotal:
Recorded investment	10,229	11,753
Unpaid principle balance	13,127	16,373
Related allowance	415	432
Residential Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Related allowance	856	795
Subtotal:
Recorded investment	12,559	13,023
Unpaid principle balance	15,292	15,802
Related allowance	$ 856	$ 795

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