Note 9 - Stock-Based Compensation - Additional Information for Stock Options (Details) - USD ($)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Weighted average fair value of options granted (in dollars per share)	$ 0.14	$ 0.43	$ 0.59
Total fair value of options vested	$ 97,707	$ 165,490	$ 319,920

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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)(1)

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

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