Capitalization And Short-Term Borrowings (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Thousands		12 Months Ended
		Sep. 30, 2015	Sep. 30, 2014
Debt Instrument [Line Items]
Total Long-Term Debt		$ 2,099,000	$ 1,649,000
Less Unamortized Discount and Debt Issuance Costs		14,991	11,557
Less Current Portion	[1]	0	0
Long-term Debt, Net of Unamortized Discount and Debt Issuance Costs		$ 2,084,009	1,637,443
7.4% Due March 2023 To June 2025 [Member]
Debt Instrument [Line Items]
Debt interest rate, minimum		7.40%
Medium-Term Notes	[2]	$ 99,000	$ 99,000
3.75% To 8.75% Due April 2018 To July 2025 [Member]
Debt Instrument [Line Items]
Debt interest rate, minimum		3.75%	3.75%
Debt interest rate, maximum		8.75%	8.75%
Notes	[2],[3]	$ 2,000,000	$ 1,550,000
Percentage of principal amount		101.00%	101.00%

[1] None of the Company’s long-term debt at September 30, 2015 and 2014 will mature within the following twelve-month period.

[2] The Medium-Term Notes and Notes are unsecured.

[3] The holders of these notes may require the Company to repurchase their notes at a price equal to 101% of the principal amount in the event of both a change in control and a ratings downgrade to a rating below investment grade.