Capitalization And Short-Term Borrowings (Summary Of Changes In Common Stock Equity) (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Sep. 30, 2022		Sep. 30, 2021	Sep. 30, 2020
Schedule of Capitalization [Line Items]
Beginning balance (shares)		91,181,549
Beginning balance		$ 1,017,446
Balance at Beginning of Year		1,191,175		$ 991,630	$ 1,272,601
Beginning balance		(513,597)		(114,757)
Net Income (Loss) Available for Common Stock		566,021		363,647	(123,772)
Dividends Declared on Common Stock		(170,111)		(164,102)	(156,249)
Other Comprehensive Loss, Net of Tax		(112,136)		(398,840)	(62,602)
Share-Based Payment Expense		$ 17,600		$ 15,200	13,100
Ending balance (Shares)		91,478,064		91,181,549
Ending balance		$ 1,027,066		$ 1,017,446
Balance at End of Year		1,587,085		1,191,175	991,630
Ending balance		$ (625,733)		$ (513,597)	$ (114,757)
Dividend per share		$ 1.86		$ 1.8	$ 1.76
Accumulated earnings free from limitations		$ 1,400,000
Common Stock [Member]
Schedule of Capitalization [Line Items]
Beginning balance (shares)		91,182,000		90,955,000	86,315,000
Beginning balance (value)		$ 91,182		$ 90,955	$ 86,315
Common Stock Issued from Sale of Common Stock (Shares)					4,370,000
Common Stock Issued from Sale of Common Stock (Value)					$ 4,370
Common Stock Issued Under Stock and Benefit Plans (Shares)		296,000		227,000	270,000
Common Stock Issued Under Stock and Benefit Plans (Value)		$ 296		$ 227	$ 270
Ending balance (Shares)		91,478,000		91,182,000	90,955,000
Ending balance (Value)		$ 91,478		$ 91,182	$ 90,955
Paid In Capital [Member]
Schedule of Capitalization [Line Items]
Beginning balance		1,017,446		1,004,158	832,264
Share-Based Payment Expense	[1]	17,699		15,297	13,180
Common Stock Issued from Sale of Common Stock (Value)					161,399
Stock Repurchased under Stock and Benefit Plans		(8,079)		(2,009)	(2,685)
Ending balance		1,027,066		1,017,446	1,004,158
Earnings Reinvested In The Business [Member]
Schedule of Capitalization [Line Items]
Balance at Beginning of Year		1,191,175		991,630	1,272,601
Net Income (Loss) Available for Common Stock		566,021		363,647	(123,772)
Dividends Declared on Common Stock		(170,111)		(164,102)	(156,249)
Balance at End of Year		1,587,085	[2]	1,191,175	991,630
Accumulated Other Comprehensive Loss [Member]
Schedule of Capitalization [Line Items]
Beginning balance		(513,597)		(114,757)	(52,155)
Other Comprehensive Loss, Net of Tax		(112,136)		(398,840)	(62,602)
Ending balance		(625,733)		(513,597)	(114,757)
Guidance for Hedging [Member] | Cumulative Effect of Adoption of Authoritative Guidance [Member]
Schedule of Capitalization [Line Items]
Balance at Beginning of Year		$ 0		0	(950)
Balance at End of Year				$ 0	0
Guidance for Hedging [Member] | Earnings Reinvested In The Business [Member] | Cumulative Effect of Adoption of Authoritative Guidance [Member]
Schedule of Capitalization [Line Items]
Balance at Beginning of Year					$ (950)

[1] Paid in Capital includes compensation costs associated with performance shares and/or restricted stock awards. The expense is included within Net Income Available for Common Stock, net of tax benefits.

[2] The availability of consolidated earnings reinvested in the business for dividends payable in cash is limited under terms of the indentures covering long-term debt. At September 30, 2022, $1.4 billion of accumulated earnings was free of such limitations.