Note 4 - Loans and Allowance for Loan Losses (Detail) - Loans Individually Evaluated for Impairment (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Unpaid Principal Balance			$ 426
With an allowance recorded:
Recorded Investment			1,979
Allowance for Loan Losses Allocated	2,112	758	2,107
Unpaid Principal Balance	18,831	17,786	19,277
Recorded Investment	16,919	15,636	17,401
Allowance for Loan Losses Allocated	2,112	758	2,107
Average Impaired Loans	17,167	13,122	11,717
Interest Income Recognized	216	243	864
Cash Basis Interest Recognized	216	207	864
Residential Real Estate Loans [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance	830	1,247	619
Recorded Investment	686	1,055	407
Average Impaired Loans	703	1,070	493
Interest Income Recognized	3	7
Cash Basis Interest Recognized	3	6
Residential Real Estate Loans [Member] \| Related Allowance Recorded (Member)
With an allowance recorded:
Unpaid Principal Balance	426		420
Recorded Investment	426		420
Allowance for Loan Losses Allocated	133		128
Average Impaired Loans	423		420
Interest Income Recognized	4		23
Cash Basis Interest Recognized	4		23
Allowance for Loan Losses Allocated	133		128
Commercial Real Estate Owner Occupied [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance	5,644	9,984	5,528
Recorded Investment	5,098	9,737	5,528
Average Impaired Loans	5,313	7,604	4,729
Interest Income Recognized	72	166	338
Cash Basis Interest Recognized	72	143	338
Commercial Real Estate Owner Occupied [Member] \| Related Allowance Recorded (Member)
With an allowance recorded:
Unpaid Principal Balance		1,571
Recorded Investment		1,571
Allowance for Loan Losses Allocated		758
Average Impaired Loans		996
Interest Income Recognized		27
Cash Basis Interest Recognized		18
Allowance for Loan Losses Allocated		758
Commercial Real Estate Nonowner Occupied [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance	7,849	3,440	10,085
Recorded Investment	7,049	2,293	8,847
Average Impaired Loans	7,052	2,458	4,767
Interest Income Recognized	93	24	456
Cash Basis Interest Recognized	93	22	456
Commercial Real Estate Nonowner Occupied [Member] \| Related Allowance Recorded (Member)
With an allowance recorded:
Unpaid Principal Balance	3,441		1,979
Recorded Investment	3,441		1,979
Allowance for Loan Losses Allocated	1,979		1,979
Average Impaired Loans	3,456		1,132
Interest Income Recognized	41		38
Cash Basis Interest Recognized	41		38
Allowance for Loan Losses Allocated	1,979		1,979
Commercial and Industrial [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance	422
With an allowance recorded:
Unpaid Principal Balance		614
Recorded Investment		329
Average Impaired Loans		331
Interest Income Recognized		10
Cash Basis Interest Recognized		9
Home Equity Loans [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance	219	220	220
Recorded Investment	219	220	220
Average Impaired Loans	220	110	176
Interest Income Recognized	3	3	9
Cash Basis Interest Recognized	3	3	9
Construction [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance		674
Recorded Investment		395
Average Impaired Loans		535
Interest Income Recognized		5
Cash Basis Interest Recognized		5
Consumer Loans [Member] \| No Related Allowance Recorded (Member)
Unpaid Principal Balance		36
Recorded Investment		36
Average Impaired Loans		18
Interest Income Recognized		1
Cash Basis Interest Recognized		$ 1

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

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Average 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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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 15

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-Paragraph 14A

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