Common stock reserved for issuance under stock holders incentive plan.

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Section S99

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-Subparagraph (SAB TOPIC 14.F)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.29)

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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.

+ References

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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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)

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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-Publisher FASB

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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

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.

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-Publisher FASB

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stockholders' Equity - Additional Information (Detail) (USD $)	3 Months Ended			0 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013	Feb. 19, 2014	Jan. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 6,849,905
Weighted average period for unrecognized compensation expense expected to be recognized	2 years 10 months 24 days
Options outstanding	3,523,065	2,334,326	2,754,030
Recognized compensation expense	814,060		829,071
Total intrinsic value of options exercised	4,083		336,340
Weighted-average remaining contractual term	7 years 2 months 27 days	5 years 5 months 16 days	7 years 1 month 6 days
Weighted-average exercise price, outstanding shares	$ 3.52	$ 4.11	$ 4.16
Aggregate intrinsic value, outstanding shares	3,138,317		7,313,083
Recognized stock-based compensation expense related to the outstanding RSUs	339,970us-gaap_RestrictedStockExpense		264,749us-gaap_RestrictedStockExpense
2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of common stock	2,044,821
Number of common stock reserved for future grants	1,479,773
Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock reserved for future grants	474,336
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance under stock holders incentive plan				2,000,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance under stock holders incentive plan				4,000,000
Maximum [Member] \| Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved for issuance					1,000,000
Restricted Stock Units (RSUs) [Member] \| 2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding	561,508
Restricted Stock Units (RSUs) [Member] \| Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding	475,000
2010 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding	1,478,244
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	3,891,848		4,775,401
Weighted average period for unrecognized compensation expense expected to be recognized	2 years 10 months 24 days		2 years 6 months
Recognized compensation expense	474,091		564,322
Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	2,958,057
Weighted average period for unrecognized compensation expense expected to be recognized	2 years 9 months 18 days
Outstanding Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 4,605,913
Weighted average period for unrecognized compensation expense expected to be recognized			3 years 6 months