Capitalization And Short-Term Borrowings (Schedule Of Share-Based Compensation For Share Awards) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Performance Shares [Member]
Schedule of Capitalization [Line Items]
Number of Shares Outstanding, Beginning of Year	600,634
Number of Shares Granted	195,397	309,470	254,608
Number of Awards Vested	(265,607)
Number of Shares Forfeited	(23,414)
Change in Units Based on Performance Achieved	100,169
Number of Shares Outstanding, End of Year	607,179	600,634
Weighted Average Fair Value per Award, Beginning of Year	$ 45.13
Weighted Average Fair Value per Award Granted	65.39	$ 39.19	$ 43.32
Weighted Average Fair Value per Award Vested	55.93
Weighted Average Fair Value per Award Forfeited	49.84
Weighted Average Fair Value per Award, Change in Units Based on Performance Achieved	56.36
Weighted Average Fair Value per Award, End of Year	$ 48.60	$ 45.13
Stock Appreciation Rights (SARs) [Member]
Schedule of Capitalization [Line Items]
Number of Shares Outstanding, Beginning of Year	318,445
Number of Shares Granted	0	0	0
Number of Shares Exercised	(241,437)	0	0
Number of Awards Vested	0	0	0
Number of Shares Forfeited	0
Number of Shares Expired	(5,000)
Number of Shares Outstanding, End of Year	72,008	318,445
Number of SARs exercisable	72,008
Weighted Average Exercise Price, Outstanding Beginning of Year	$ 53.60
Weighted Average Exercise Price, Granted	0
Weighted Average Exercise Price, Exercised	55.73
Weighted Average Exercise Price, Forfeited	0
Weighted Average Exercise Price, Expired	55.09
Weighted Average Exercise Price, Outstanding End of Year	53.05	$ 53.60
Weighted Average Exercise Price, SARs exercisable	$ 53.05
Weighted Average Remaining Contractual Life, Outstanding	2 months 19 days
Weighted Average Remaining Contractual Life, SARs exercisable	2 months 19 days
Aggregate Intrinsic Value Outstanding	$ 612
Aggregate Intrinsic Value, SARs exercisable	$ 612