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Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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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.

+ 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

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ 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 (d)(2)

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)

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

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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Stock-Based Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock Based Compensation Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 2.51	$ 0.47	$ 0.37
Stock or Unit Option Plan Expense	$ 404,150us-gaap_StockOptionPlanExpense	$ 704,480us-gaap_StockOptionPlanExpense	$ 63,385us-gaap_StockOptionPlanExpense
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	914,824
Research and Development Expense
Stock Based Compensation Plans [Line Items]
Stock or Unit Option Plan Expense	83,139
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options	705,387
2007 Stock Incentive Plan
Stock Based Compensation Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	8,423,787
Director Service Stock Option
Stock Based Compensation Plans [Line Items]
Stock or Unit Option Plan Expense	$ 321,011