9. Stockholders' Equity (Details-Stock Option Activity) (Stock Options [Member], USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock Options [Member]
Outstanding Options
Options outstanding, beginning balance	2,664,000	1,814,000
Options granted	5,581,000	1,280,000
Options exercised	(291,000)	(30,000)
Options cancelled	(89,000)	(245,000)
Options forfeited	(642,000)	(102,000)
Options expired	(1,000)	(53,000)
Options outstanding, ending balance	7,222,000	2,664,000	1,814,000
Options vested and exercisable	1,562,000
Weighted average exercise price per share
Options outstanding, beginning balance	$ 0.50	$ 0.66
Options granted	$ 0.47	$ 0.27
Options exercised	$ 0.25	$ 0.17
Options cancelled	$ 1.11	$ 0.49
Options forfeited	$ 0.27	$ 0.19
Options expired	$ 3.15	$ 1.09
Options outstanding, ending balance	$ 0.50	$ 0.50	$ 0.66
Options vested and exercisable	$ 0.76
Weighted average remaining contractual life
Options outstanding, ending balance	8 years 7 months 6 days	7 years 1 month 20 days	6 years 4 months 13 days
Options vested and exercisable	5 years 3 months 7 days
Aggregate Intrinsic Value
Options outstanding, beginning balance	$ 706,000	$ 25,000
Options outstanding, ending balance	285,000	706,000	25,000
Options vested and exercisable	$ 99,000

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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