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.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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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- Definition

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

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No definition available.

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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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Stock Award Plans - Additional Information (Details) - USD ($)	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to be reserved (in shares)	5,000,000
Shares available for issuance (in shares)	3,281,946
Award vesting period (in years)	5 years
Contractual term of award (in years)	10 years
Options granted (in shares)	0	0	0
Unrecognized compensation cost for stock options, net of forfeitures	$ 0
Compensation cost for stock options	$ 0	$ 0	$ 89,000
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, nonvested (in shares)	460,999	466,681	490,363	521,302
Fair market value at date of grant at restricted stock	$ 10,381,697
Compensation cost for stock options	$ 4,259,458	$ 3,658,539	$ 3,357,108
Minimum \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	1 year
Maximum \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	7 years