Note 13 - Stock Option Plan (Details) - Tax Benefits and Intrinsic Value Related to Stock Options Exercised (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Tax Benefits and Intrinsic Value Related to Stock Options Exercised [Abstract]
Tax benefits related to stock options exercised	$ 29	$ 2
Intrinsic value of stock options exercised	$ 161	$ 91

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration