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The Company's debt to capitalization ratio at the balance sheet date.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value amount of debt instrument that was repurchased.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of cost capitalized for award under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Unamortized Loss on Reacquired Debt is the loss incurred upon reacquisition or refinancing of debt, is treated as a deferred charge and amortized over the life of the new debt issued.

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Capitalization And Short-Term Borrowings (Narrative) (Details)		3 Months Ended	12 Months Ended
	Aug. 17, 2018 USD ($)	Sep. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2017 USD ($) $ / shares shares	Sep. 07, 2018 USD ($)	Sep. 27, 2017 USD ($)
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			126,879
Shares tendered \| shares			159,413
Share-Based Payment Expense			$ 19,500,000	$ 14,200,000	$ 10,800,000
Tax benefit related to stock-based compensation expense			3,800,000	3,400,000	4,400,000
Capitalized stock-based compensation costs			100,000	100,000	100,000
Tax benefit from stock-based compensation exercises and vestings			3,200,000
Unamortized Debt Expense		$ 14,005,000	14,005,000	15,975,000
Gain (Loss) on Extinguishment of Debt				1,000,000.0
Net proceeds from issuance of long-term debt			0	295,020,000	$ 295,151,000
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		500,000,000.0	500,000,000.0
Principal amounts of long-term debt maturing in 2023		549,000,000.0	549,000,000.0
Principal amounts of long-term debt maturing in 2024		0	0
Principal amounts of long-term debt maturing after 2024		1,100,000,000.0	1,100,000,000.0
Commercial paper, outstanding		$ 55,200,000	$ 55,200,000	0
Weighted average interest rate on commercial paper		2.50%	2.50%
Short-term notes payable outstanding		$ 0	$ 0	$ 0
Committed credit facility maximum 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			0.51
Additional borrowing		1,780,000,000	$ 1,780,000,000
Aggregated indebtedness			$ 40,000,000.0
Maximum debt increase under existing indenture covenants		$ 1,020,000,000.00
Preferred stock, shares authorized \| shares		10,000,000	10,000,000
Preferred stock par value \| $ / shares		$ 1	$ 1
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			$ 7,200,000	$ 4,400,000	$ 1,600,000
Number of Awards Vested \| shares			0	0	5,000
Equity instruments other than options, vested in period, total fair value					$ 100,000
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
Number of Awards Vested \| shares			0
Unrecognized compensation expense		$ 100,000	$ 100,000
Unrecognized compensation expense recognized weighted average period			1 year 1 month 6 days
Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Number of Shares Granted \| shares			123,939	89,672	87,143
Weighted Average Fair Value per Award Granted \| $ / shares			$ 49.40	$ 51.23	$ 52.13
Number of Awards Vested \| shares			80,354
Unrecognized compensation expense		6,100,000	$ 6,100,000
Unrecognized compensation expense recognized weighted average period			2 years 3 months 18 days
Performance Shares [Member]
Debt Instrument [Line Items]
Common stock issued \| shares			281,882
Number of Shares Granted \| shares			244,734	208,588	184,148
Weighted Average Fair Value per Award Granted \| $ / shares			$ 55.67	$ 50.95	$ 56.39
Number of Awards Vested \| shares			281,882
Unrecognized compensation expense		8,700,000	$ 8,700,000
Unrecognized compensation expense recognized weighted average period			1 year 8 months 12 days
Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Common stock issued \| shares			80,354
Board Of Directors [Member]
Debt Instrument [Line Items]
Common stock issued \| shares			28,771
3.95% Notes Due September 15, 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, face value							$ 300,000,000.0
Long-term debt, interest rate							3.95%
4.75% Notes Due September 1, 2028 [Member]
Debt Instrument [Line Items]
Long-term debt, face value	$ 300,000,000.0
Long-term debt, interest rate	4.75%
Net proceeds from issuance of long-term debt	$ 295,000,000.0
8.75% Notes Due May 2019 [Member]
Debt Instrument [Line Items]
Long-term debt, face value						$ 250,000,000.0
Long-term debt, interest rate						8.75%
Debt Instrument redeemed				$ 259,500,000
Unamortized Debt Expense				8,500,000
6.50% Notes Due April 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, face value				$ 300,000,000.0
Long-term debt, interest rate				6.50%
Debt Instrument redeemed				$ 307,000,000.0
Indenture From 1974 [Member]
Debt Instrument [Line Items]
Carrying Amount		99,000,000.0	$ 99,000,000.0
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper available		500,000,000.0	500,000,000.0
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
2020 [Member] \| Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			87,835
2020 [Member] \| Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			173,454
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			76,146
2021 [Member] \| Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			170,526
2022 [Member] \| Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			67,525
2022 [Member] \| Performance Shares [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			178,534
2023 [Member] \| Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			33,831
2024 [Member] \| Non-Performance Based Restricted Stock Units (RSUs) [Member]
Debt Instrument [Line Items]
Non-vested stock-based compensation lapse \| shares			16,270