Note 7 - Stock-Based Compensation (Details) - Unreleased Restricted Stock Awards (Restricted Stock [Member], USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Restricted Stock [Member]
Note 7 - Stock-Based Compensation (Details) - Unreleased Restricted Stock Awards [Line Items]
Number of Shares Unreleased	3,625,457	3,625,457	2,677,820	3,938,426
Weighted Average Grant Date Fair Value	$ 0.24	$ 0.24	$ 0.31	$ 0.28
Weighted Average Remaining Recognition Period (Years)	2 years 87 days	2 years 87 days
Unrecognized Compensation Cost Remaining	$ 749,100	$ 749,100
Number of Awarded Shares	1,767,000	2,152,000
Awarded Shares, Weighted Average Grant Date Fair Value	$ 0.17	$ 0.19
Number of Released Shares	(342,135)	(818,394)
Released Shares, Weighted Average Grant Date Fair Value	$ 0.27	$ 0.27
Number of Forfeited Shares	(477,228)	(1,646,575)
Forfeited Shares, Weighted Average Grant Date Fair Value	$ 0.34	$ 0.26

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Unrecognized cost of unvested share-based compensation awards.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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