Share-Based Compensation - Schedule Of Outstanding Restricted Share Awards (Details) - $ / shares	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Share-Based Compensation
Outstanding restricted share awards, Nonvested at October 1,	220,300	281,004	315,544
Outstanding restricted share awards, Granted, Shares	51,476	45,723	84,862
Outstanding restricted share awards, Vested, Shares	(35,753)	(89,822)	(113,402)
Outstanding restricted share awards, Cancelled, Shares	(9,318)	(16,605)	(6,000)
Outstanding restricted share awards, Nonvested at September 30,	226,705	220,300	281,004
Outstanding restricted share awards, Nonvested at October 1, Weighted Avg. Price	$ 66.55	$ 59.72	$ 47.23
Outstanding restricted share awards, Granted, Weighted Avg. Price	108.05	74.80	74.77
Outstanding restricted share awards, Vested, Weighted Avg. Price	64.40	50.51	37.00
Outstanding restricted share awards, Cancelled, Weighted Avg. Price	70.50	60.48	45.20
Outstanding restricted share awards, Nonvested at September 30, Weighted Avg. Price	$ 76.15	$ 66.55	$ 59.72

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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