Stock Option Plans and Warrants to Purchase Common Stock (Details 2) (Employee Stock Option [Member], USD $)	12 Months Ended
Dec. 31, 2014
Weighted-average Range of Exercise Prices for options/warrants outstanding and exercisable
Weighted-Average Remaining Contractual Life in Years	6 years 10 months 24 days
Outstanding Options/Warrants	2,488,279
Exercisable Options/Warrants	1,875,609
$0.30-$2.20 [Member]
Weighted-average Range of Exercise Prices for options/warrants outstanding and exercisable
Exercise price range, lower range limit	0.30
Exercise price range, upper range limit	2.20
Weighted-Average Remaining Contractual Life in Years	7 years 8 months 12 days
Outstanding Options/Warrants	1,805,755
Exercisable Options/Warrants	1,193,081
$2.26-$4.10 [Member]
Weighted-average Range of Exercise Prices for options/warrants outstanding and exercisable
Exercise price range, lower range limit	2.26
Exercise price range, upper range limit	4.10
Weighted-Average Remaining Contractual Life in Years	6 years 10 months 24 days
Outstanding Options/Warrants	174,774
Exercisable Options/Warrants	174,778
$4.64-$9.40[Member]
Weighted-average Range of Exercise Prices for options/warrants outstanding and exercisable
Exercise price range, lower range limit	4.64
Exercise price range, upper range limit	9.40
Weighted-Average Remaining Contractual Life in Years	3 years 8 months 12 days
Outstanding Options/Warrants	507,750
Exercisable Options/Warrants	507,750

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)

-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 exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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)(iii)

-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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- Definition

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.

+ 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 (e)(1)

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

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

+ Details

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