9. Stock-Based Compensation - Ranges for options outstanding (Details 1) (USD $)	12 Months Ended
Dec. 31, 2014
Outstanding at end of year, Shares	1,390,770
Weighted Average Remaining Contractual Life	4 years 11 months 12 days
Wtd. Avg Exercise Price
Outstanding at end of year	$ 1.50
0.49-$1.00
Outstanding at end of year, Shares	167,853
Weighted Average Remaining Contractual Life	2 years 11 months 12 days
Wtd. Avg Exercise Price
Outstanding at end of year	$ 0.92
1.01-$1.30
Outstanding at end of year, Shares	758,507
Weighted Average Remaining Contractual Life	4 years 5 months 5 days
Wtd. Avg Exercise Price
Outstanding at end of year	$ 1.14
1.31-$2.00
Outstanding at end of year, Shares	333,699
Weighted Average Remaining Contractual Life	5 years 6 months 4 days
Wtd. Avg Exercise Price
Outstanding at end of year	$ 1.43
2.01-$10.50
Outstanding at end of year, Shares	130,711
Weighted Average Remaining Contractual Life	9 years 1 month 24 days
Wtd. Avg Exercise Price
Outstanding at end of year	$ 4.49

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

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

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