Capitalization And Short-Term Borrowings (Narrative) (Details)			3 Months Ended	12 Months Ended
	Aug. 17, 2018 USD ($)	Sep. 27, 2017 USD ($)	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2017 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) $ / shares shares	Sep. 07, 2018 USD ($)	Oct. 18, 2017 USD ($)
Debt Instrument [Line Items]
Issue shares of common stock for the Direct Stock Purchase and Dividend Reinvestment Plan | shares				138,997
Common stock issued for 401(k) plans | shares				75,745
Common stock shares issued due to SARs exercises | shares				75,971
Shares tendered | shares				57,065
Share-Based Payment Expense				$ 14,200,000	$ 10,800,000	$ 4,800,000
Tax benefit related to stock-based compensation expense				3,400,000	4,400,000	1,900,000
Capitalized stock-based compensation costs				100,000	100,000	100,000
Tax benefit from stock-based compensation exercises and vestings				1,000,000
Unamortized Debt Expense			$ 15,975,000	15,975,000	1,159,000
Gain (Loss) on Extinguishment of Debt				1,000,000
Net proceeds from issuance of long-term debt				295,020,000	295,151,000	$ 0
Principal amounts of long-term debt maturing in 2019			0	0
Principal amounts of long-term debt maturing in 2020			0	0
Principal amounts of long-term debt maturing in 2021			0	0
Principal amounts of long-term debt maturing in 2022			500,000,000	500,000,000
Principal amounts of long-term debt maturing in 2023			549,000,000	549,000,000
Principal amounts of long-term debt maturing after 2023			1,100,000,000	1,100,000,000
Commercial paper, outstanding			0	0	0
Short-term notes payable outstanding			$ 0	$ 0	0
Committed credit facility debt to capitalization ratio				0.65
Ceiling Test Impairment Adjustment			50.00%	50.00%
Ceiling Test Impairment Maximum Adjustment			$ 250,000,000	$ 250,000,000
Debt to capitalization ratio				0.52
Additional borrowing			1,460,000,000	$ 1,460,000,000
Aggregated indebtedness				$ 40,000,000
Maximum debt increase under existing indenture covenants			$ 714,000,000
Preferred stock, shares authorized | shares			10,000,000	10,000,000
Preferred stock par value | $ / shares			$ 1	$ 1
Carrying Amount			$ 2,131,365,000	$ 2,131,365,000	$ 2,383,681,000
Percentage of Long-Term Debt issued under 1974 Indenture				4.60%
Stock Appreciation Rights (SARs) [Member]
Debt Instrument [Line Items]
Number of Shares Granted | shares				0	0	0
Total intrinsic value of SAR's exercised				$ 4,400,000	$ 1,600,000	$ 400,000
Number of Awards Vested | shares				0	5,000	113,082
Equity instruments other than options, vested in period, total fair value					$ 100,000	$ 1,200,000
Restricted Share Awards [Member]
Debt Instrument [Line Items]
Number of Shares Granted | shares				0	0	0
Weighted Average Fair Value per Award Granted | $ / shares				$ 0.00
Number of Awards Vested | shares				0
Unrecognized compensation expense			200,000	$ 200,000
Unrecognized compensation expense recognized weighted average period				2 years 1 month 13 days
Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Number of Shares Granted | shares				89,672	87,143	101,943
Weighted Average Fair Value per Award Granted | $ / shares				$ 51.23	$ 52.13	$ 35.89
Number of Awards Vested | shares				72,918
Unrecognized compensation expense			5,000,000	$ 5,000,000
Unrecognized compensation expense recognized weighted average period				2 years 2 months 13 days
Performance Shares [Member]
Debt Instrument [Line Items]
Common stock issued | shares				79,079
Number of Shares Granted | shares				208,588	184,148	309,996
Weighted Average Fair Value per Award Granted | $ / shares				$ 50.95	$ 56.39	$ 30.71
Number of Awards Vested | shares				79,079
Unrecognized compensation expense			11,200,000	$ 11,200,000
Unrecognized compensation expense recognized weighted average period				1 year 8 months 10 days
Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Common stock issued | shares				72,918
Board Of Directors [Member]
Debt Instrument [Line Items]
Common stock issued | shares				28,044
3.95% Notes Due September 15, 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, face value		$ 300,000,000
Long-term debt, interest rate		3.95%
Net proceeds from issuance of long-term debt		$ 295,200,000
4.75% Notes Due September 1, 2028 [Member]
Debt Instrument [Line Items]
Long-term debt, face value	$ 300,000,000
Long-term debt, interest rate	4.75%
Net proceeds from issuance of long-term debt	$ 295,000,000
8.75% Notes Due May 2019 [Member]
Debt Instrument [Line Items]
Long-term debt, face value							$ 250,000,000
Long-term debt, interest rate							8.75%
Debt Instrument redeemed			259,500,000	$ 259,500,000
Unamortized Debt Expense			8,500,000	8,500,000
6.50% Notes Due April 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, face value					$ 300,000,000
Long-term debt, interest rate					6.50%
Debt Instrument redeemed								$ 307,000,000
Indenture From 1974 [Member]
Debt Instrument [Line Items]
Carrying Amount			99,000,000	99,000,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper available			500,000,000	500,000,000
Fourth Amended & Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 750,000,000.0	$ 750,000,000.0
2019 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				80,354
2019 [Member] | Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				253,704
2020 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				68,189
2020 [Member] | Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				181,446
2021 [Member] | Restricted Share Awards [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				20,000
2021 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				57,175
2021 [Member] | Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				206,140
2022 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				26,448
2023 [Member] | Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse | shares				13,150