14. Stock-Based Compensation (Details 2) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Number of Shares
Outstanding	2,147,561	2,130,239
Granted	2,578,000	498,000
Exercised	(26,865)	(28,418)
Cancelled/forfeited	(317,998)	(452,260)
Outstanding	4,380,698	2,147,561
Shares vested and expected to vest	4,052,341
Exercisable	2,716,262	1,351,894
Weighted-Average Exercise Price
Outstanding	$ 3.78	$ 3.96
Granted	1.50	3.18
Exercised	1.85	2.44
Cancelled/forfeited	2.16	4.05
Outstanding	2.56	3.78
Shares vested and expected to vest	2.56
Exercisable	$ 3.04	$ 4.18
Weighted-Average Remaining Contract Life
Outstanding	6 years 10 months 24 days	8 years
Outstanding	6 years 2 months 12 days	6 years 10 months 24 days
Shares vested and expected to vest	6 years 2 months 12 days
Exercisable	6 years 1 month 6 days	6 years 7 months 6 days
Aggregate Intrinsic Value
Outstanding	$ 0	$ 482
Outstanding	0	0
Shares vested and expected to vest	0
Exercisable	$ 0	$ 0

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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