Narrative (Details) (USD $)	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from warrant exercises	$ 0	$ 226,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options modified to allow continued vesting	84,758
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Unamortized Compensation Cost, Stock Options	7,400,000
Uamortized Compensation Cost Not yet Recognized, Period Remaining, Options	2 years 10 months 21 days
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	0
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	11,500,000
Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized	2 years 1 month 24 days
Restricted stock units modified to allow continued vesting	35,528
2012 Stock Option Plan \| Stock options and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Available for Grant	419,743
2012 Employee Stock Purchase Plan \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Available for Grant	356,945
ESPP plan details [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award	86,646	115,784
Cash Exercise
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued, Exercise of Stock Warrants	0	34,142
Proceeds from warrant exercises		$ 200,000
Year to date \| 2012 Employee Stock Purchase Plan \| ESPP
ESPP plan details [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased	$ 10.91	$ 13.79

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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

-Subparagraph (i)

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

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The cash inflow associated with the amount received from holders exercising their stock warrants.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the 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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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The number of shares purchased on the open market during the period for issuance to employees under the plan.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Modified to Allow Continued Vesting

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Modified to Allow Continued Vesting

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Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized

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Stock Issued During Period, Shares, Exercise of Stock Warrants

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