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Capitalization (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2023	Nov. 25, 2022	Sep. 30, 2022
Debt Instrument [Line Items]
Common stock shares issued due to SARs exercises	12,055
Shares tendered	102,761
Current Portion of Long-Term Debt	$ 0		$ 549,000
364-Day Credit Agreement
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	250,000
Committed Credit Facility Amount Drawn	250,000
3.75% Notes Due March 2023 [Member]
Debt Instrument [Line Items]
Debt instrument redeemed	$ 350,000	$ 150,000
Current Portion of Long-Term Debt			$ 500,000
Long-term debt, interest rate	3.75%	3.75%	3.75%
7.395% Notes Due March 2023 [Member]
Debt Instrument [Line Items]
Debt instrument redeemed	$ 49,000
Current Portion of Long-Term Debt			$ 49,000
Long-term debt, interest rate	7.395%		7.395%
Restricted Stock Units [Member]
Debt Instrument [Line Items]
Common stock issued	113,531
Performance Shares [Member]
Debt Instrument [Line Items]
Common stock issued	278,687
Board Of Directors [Member]
Debt Instrument [Line Items]
Common stock issued	14,680
Officer DCP Plan [Member]
Debt Instrument [Line Items]
Common stock issued	824