11. Stock-Based Compensation (Details 3) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Dividend-yield	0.00%
Minimum
Risk-free interest rate	0.89%
Expected volatility	77.00%
Expected life (years)	2 years 6 months
Maximum
Risk-free interest rate	1.10%
Expected volatility	77.78%
Expected life (years)	3 years
Equity Option [Member]
Dividend-yield	0.00%	0.00%	0.00%
Expected volatility			79.08%
Expected life (years)	3 years	3 years
Market value per share on grant date			$ 5.50
Equity Option [Member] \| Minimum
Risk-free interest rate	0.74%	0.42%	0.28%
Expected volatility	77.00%	73.20%
Expected life (years)			2 years
Market value per share on grant date	4.20	4.00
Weighted average fair value per share of common stock	2.14	1.92	$ 2.34
Equity Option [Member] \| Maximum
Risk-free interest rate	1.10%	0.63%	0.38%
Expected volatility	78.43%	75.55%
Expected life (years)			3 years
Market value per share on grant date	4.66	6.50
Weighted average fair value per share of common stock	2.35	3.19	$ 2.80

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+ References

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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