Capitalization And Short-Term Borrowings (Narrative) (Details)					12 Months Ended
		Feb. 24, 2021 USD ($)	Jun. 03, 2020 USD ($)	Jun. 02, 2020 USD ($) $ / shares shares	Sep. 30, 2022 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares	Oct. 27, 2022 USD ($)	Mar. 11, 2021 USD ($)
Debt Instrument [Line Items]
Issue shares of common stock for the Direct Stock Purchase and Dividend Reinvestment Plan | shares					0
Common stock issued for 401(k) plans | shares					0
Common stock shares issued due to SARs exercises | shares					30,769
Shares tendered | shares					157,812
Share-Based Payment Expense					$ 17,600,000	$ 15,200,000	$ 13,100,000
Tax benefit related to stock-based compensation expense					2,500,000	2,400,000	2,100,000
Capitalized stock-based compensation costs					100,000	100,000	100,000
Gain (Loss) on Extinguishment of Debt					0	(15,715,000)	0
Net proceeds from issuance of long-term debt					0	495,267,000	$ 493,007,000
Principal amounts of long-term debt maturing in 2023					549,000,000
Principal amounts of long-term debt maturing in 2024					0
Principal amounts of long-term debt maturing in 2025					500,000,000
Principal amounts of long-term debt maturing in 2026					500,000,000
Principal amounts of long-term debt maturing in 2027					300,000,000
Principal amounts of long-term debt maturing after 2027					800,000,000
Commercial paper, outstanding					0	158,500,000
Short-term notes payable outstanding					$ 60,000,000	$ 0
Committed credit facility maximum debt to capitalization ratio					0.65
Ceiling Test Impairment Adjustment					50.00%
Ceiling Test Impairment Maximum Adjustment					$ 400,000,000
Debt to capitalization ratio					0.49
Additional borrowing					$ 2,560,000,000
Aggregated indebtedness					40,000,000
Maximum debt increase under existing indenture covenants					$ 2,000,000,000
Preferred stock, shares authorized | shares					10,000,000
Preferred stock par value | $ / shares					$ 1
Percentage of Long-Term Debt issued under 1974 Indenture					3.70%
Common Stock, Par Value | $ / shares					$ 1	$ 1
Cumulative after-tax ceiling test impairments since July 1, 2018					$ 381,400,000
Committed Credit Facility Debt to Capitalization Ratio Ceiling Test Impairment Adjustment Amount					190,700,000
Debt to Capitalization Ratio Maximum Excluded Unrealized Gains or Losses on Other Derivative Financial Instruments in AOCI					10,000,000
Tax benefit related to stock-based compensation exercises and vestings					$ 600,000
Number of Shares available for future grant | shares					2,149,203
Maximum Long-Term Debt To Consolidated Asset Ratio under Indenture					60.00%
Indenture Period before Debt Issuance					15 months
Indenture Test Period					12 months
Current Portion of Long-Term Debt	[1]				$ 549,000,000	$ 0
June 2, 2020 Public Offering of Common Stock [Member]
Debt Instrument [Line Items]
Common Stock Issued from Sale of Common Stock (Shares) | shares				4,370,000
Common Stock, Par Value | $ / shares				$ 1.00
Common Stock Issued, Price Per Share | $ / shares				$ 39.50
Proceeds from Issuance of Common Stock				$ 165,800,000
Stock Appreciation Rights (SARs) [Member]
Debt Instrument [Line Items]
Number of Shares Granted | shares					0	0	0
Total intrinsic value of SAR's exercised					$ 2,000,000
Number of Awards Vested | shares					0	0	0
Number of Awards Exercised | shares					(241,437)	0	0
Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Number of Shares Granted | shares					128,950	172,513	150,839
Weighted Average Fair Value per Award Granted | $ / shares					$ 54.10	$ 37.98	$ 40.38
Number of Awards Vested | shares					129,169
Unrecognized compensation expense					$ 6,400,000
Unrecognized compensation expense recognized weighted average period					2 years 2 months 12 days
Performance Shares [Member]
Debt Instrument [Line Items]
Common stock issued | shares					265,607
Number of Shares Granted | shares					195,397	309,470	254,608
Weighted Average Fair Value per Award Granted | $ / shares					$ 65.39	$ 39.19	$ 43.32
Number of Awards Vested | shares					265,607
Unrecognized compensation expense					$ 11,300,000
Unrecognized compensation expense recognized weighted average period					1 year 9 months 18 days
Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Common stock issued | shares					129,169
Board Of Directors [Member]
Debt Instrument [Line Items]
Common stock issued | shares					28,782
5.50% Notes Due January 15, 2026 [Member]
Debt Instrument [Line Items]
Long-term debt, face value			$ 500,000,000
Long-term debt, interest rate			5.50%
Net proceeds from issuance of long-term debt			$ 493,000,000
Indenture From 1974 [Member]
Debt Instrument [Line Items]
Carrying Amount					$ 99,000,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper available					$ 500,000,000
Weighted average interest rate						0.40%
2.95% Notes Due March 1, 2031 [Member]
Debt Instrument [Line Items]
Long-term debt, face value		$ 500,000,000
Long-term debt, interest rate		2.95%
Net proceeds from issuance of long-term debt		$ 495,300,000
4.90% Notes Due December 1, 2021 [Member]
Debt Instrument [Line Items]
Long-term debt, face value									$ 500,000,000
Long-term debt, interest rate									4.90%
Debt Instrument redeemed						$ 515,700,000
Gain (Loss) on Extinguishment of Debt						$ (15,700,000)
Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Weighted average interest rate					4.02%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					$ 1,000,000,000
364-Day Credit Agreement
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					$ 250,000,000
364-Day Credit Agreement | Subsequent Event [Member]
Debt Instrument [Line Items]
Committed credit facility amount drawn								$ 250,000,000
2023 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					119,612
2023 [Member] | Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					199,842
2024 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					97,614
2024 [Member] | Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					220,914
2025 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					73,797
2025 [Member] | Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					186,423
2026 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					37,052
2027 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares					19,352

[1] Current Portion of Long-Term Debt at September 30, 2022 consists of $500.0 million of 3.75% notes and $49.0 million of 7.395% notes that each mature in March 2023. The Company has committed to redeeming $150.0 million of the 3.75% notes on November 25, 2022. None of the Company's long-term debt as of September 30, 2021 had a maturity date within the following twelve-month period.