Note 6 - Loans Receivable and Allowance for Loan Losses (Details) - Activity in Allowance for Loan Losses (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Allowance for loan losses:
Beginning balance	$ 11,536	$ 12,263
Charge-offs	(677)	(313)
Recoveries	85	0
Provisions (credits)	0us-gaap_ProvisionForLoanAndLeaseLosses	0us-gaap_ProvisionForLoanAndLeaseLosses
Ending balance	10,944	11,950
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	4,971		5,130
Allowance for loan losses: collectively evaluated for impairment	5,973		6,406
Total allowance for loan losses	10,944	11,950
Loans receivable:
Loans receivable: loans evaluated individually	36,294		35,644
Loans receivable: loans evaluated collectively	752,816		746,735
Total loans receivable	789,110		782,379
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses:
Beginning balance	6,828	6,454
Charge-offs	(231)	0
Recoveries	4	0
Provisions (credits)	(338)	(180)
Ending balance	6,263	6,274
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	3,838		3,858
Allowance for loan losses: collectively evaluated for impairment	2,425		2,970
Total allowance for loan losses	6,263	6,274
Loans receivable:
Loans receivable: loans evaluated individually	24,777		25,082
Loans receivable: loans evaluated collectively	339,620		354,177
Total loans receivable	364,397		379,259
Commercial Real Estate Construction Financing Receivable [Member]
Allowance for loan losses:
Beginning balance	917	1,948
Charge-offs	(222)	(20)
Recoveries	5	0
Provisions (credits)	(445)	(1,067)
Ending balance	255	861
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	0		217
Allowance for loan losses: collectively evaluated for impairment	255		700
Total allowance for loan losses	255	861
Loans receivable:
Loans receivable: loans evaluated individually	155		377
Loans receivable: loans evaluated collectively	35,083		29,484
Total loans receivable	35,238		29,861
Commercial Portfolio Segment [Member]
Allowance for loan losses:
Beginning balance	1,579	2,309
Charge-offs	(169)	(283)
Recoveries	45	0
Provisions (credits)	469	614
Ending balance	1,924	2,640
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	294		211
Allowance for loan losses: collectively evaluated for impairment	1,630		1,368
Total allowance for loan losses	1,924	2,640
Loans receivable:
Loans receivable: loans evaluated individually	5,502		5,221
Loans receivable: loans evaluated collectively	154,317		139,892
Total loans receivable	159,819		145,113
Owner Occupied Real Estate [Member]
Allowance for loan losses:
Beginning balance	1,638	985
Charge-offs	(55)	0
Recoveries	0	0
Provisions (credits)	(5)	143
Ending balance	1,578	1,128
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	839		844
Allowance for loan losses: collectively evaluated for impairment	739		794
Total allowance for loan losses	1,578	1,128
Loans receivable:
Loans receivable: loans evaluated individually	5,287		4,535
Loans receivable: loans evaluated collectively	183,496		183,490
Total loans receivable	188,783		188,025
Consumer Other Financing Receivable [Member]
Allowance for loan losses:
Beginning balance	234	225
Charge-offs	0	(10)
Recoveries	31	0
Provisions (credits)	(35)	(18)
Ending balance	230	197
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	0		0
Allowance for loan losses: collectively evaluated for impairment	230		234
Total allowance for loan losses	230	197
Loans receivable:
Loans receivable: loans evaluated individually	573		429
Loans receivable: loans evaluated collectively	39,895		39,284
Total loans receivable	40,468		39,713
Residential Portfolio Segment [Member]
Allowance for loan losses:
Beginning balance	2	14
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	0	(1)
Ending balance	2	13
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	0		0
Allowance for loan losses: collectively evaluated for impairment	2		2
Total allowance for loan losses	2	13
Loans receivable:
Loans receivable: loans evaluated individually	0		0
Loans receivable: loans evaluated collectively	405		408
Total loans receivable	405		408
Unallocated Financing Receivables [Member]
Allowance for loan losses:
Beginning balance	338	328
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	354	509
Ending balance	692	837
Allowance for loan losses:
Allowance for loan losses: individually evaluated for impairment	0		0
Allowance for loan losses: collectively evaluated for impairment	692		338
Total allowance for loan losses	692	837
Loans receivable:
Loans receivable: loans evaluated individually	0		0
Loans receivable: loans evaluated collectively	0		0
Total loans receivable	$ 0		$ 0

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A valuation allowance for financing receivables that are expected to be uncollectible.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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