Grant date fair value of the options granted during the period.

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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
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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
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

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

+ References

+ Details

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

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

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options Outstanding	5,549,543	6,691,200
Number of Options Outstanding, Granted	638,000
Stock-based compensation expense	$ 7,891,595	$ 11,595,816	$ 10,232,897
Restricted stock unit vesting, description	At vesting, each RSU will be exchanged for one share of the Company’s Common Stock. Restricted stock unit awards generally vest subject to the satisfaction of service requirements or the satisfaction of both service requirements and achievement of certain performance targets.
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 4,524,833	6,361,396	4,760,831
Grant date fair value of the options granted	849,816	6,426,207	7,338,395
Intrinsic value of options exercised	35,512	142,690	128,391
Unrecognized pre-tax compensation expense	$ 4,627,267
Weighted average period to recognize pre-tax compensation expense	1 year 9 months 19 days
Dividend yield	0.00%
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding, granted	2,623,000
Stock-based compensation expense	$ 3,366,762	$ 5,234,420	$ 4,489,931
Weighted average period to recognize pre-tax compensation expense	1 year 1 month 7 days
Unrecognized pre-tax compensation expense	$ 2,448,449
2004 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance	2,119,286
2004 Equity Incentive Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options Outstanding	2,119,286
Number of Options Outstanding, Granted	0
2004 Equity Incentive Plan \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding, granted	0
2013 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance	6,329,079
2013 Incentive Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options Outstanding	2,986,207
Number of Options Outstanding, Granted	591,000
2013 Incentive Plan \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding	3,098,000
Number of restricted stock units outstanding, granted	2,623,000
Outside Of Equity Compensation Plans
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance	444,050
Outside Of Equity Compensation Plans \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options Outstanding, Granted	47,000
Outside Of Equity Compensation Plans \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding	10,000
Number of restricted stock units outstanding, granted	0