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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-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

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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.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

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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.

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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).

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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

Share-based Compensation, Equity Awards Other than Options, Grants, Fair Value

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Share-based Compensation Arrangement by Share-based Payment Award, Maximum Contractual Term

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Share-based Compensation Arrangement by Share-based Payment Award, Number of Compensation Plans

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Stock Award Plans - Additional Information (Details)	12 Months Ended
Stock Award Plans - Additional Information (Details)	Sep. 30, 2015 USD ($) plan shares	Sep. 30, 2014 USD ($) shares	Sep. 30, 2013 USD ($) shares	Sep. 30, 2012 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of compensation plans \| plan	1
Shares authorized to be reserved \| shares	5,000,000
Shares available for issuance \| shares	4,201,230
Award vesting period (in years)	5 years
Contractual term of award (in years)	10 years
Unrecognized compensation cost for stock options, net of forfeitures	$ 95,182
Weighted average remaining period (years)	6 months
Compensation cost for stock options	$ 232,000	$ 324,000	$ 473,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, nonvested, number \| shares	521,302	515,845	480,904	371,096
Fair market value at date of grant at restricted stock	$ 7,800,000	$ 7,300,000
Compensation cost for stock options	$ 3,271,564	$ 3,085,081	$ 2,815,049
Minimum \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	1 year
Maximum \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	7 years