Capitalization And Short-Term Borrowings (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Thousands		Sep. 30, 2016	Sep. 30, 2015
Debt Instrument [Line Items]
Total Long-Term Debt		$ 2,099,000	$ 2,099,000
Less Unamortized Discount and Debt Issuance Costs		12,748	14,991
Less Current Portion	[1]	0	0
Long-term Debt, Net of Unamortized Discount and Debt Issuance Costs		2,086,252	2,084,009
7.4% Due March 2023 To June 2025 [Member]
Debt Instrument [Line Items]
Medium-Term Notes	[2]	$ 99,000	$ 99,000
Long-term debt, interest rate		7.40%	7.40%
3.75% To 8.75% Due April 2018 To July 2025 [Member]
Debt Instrument [Line Items]
Notes	[2],[3]	$ 2,000,000	$ 2,000,000
Percentage of principal amount		101.00%	101.00%
Minimum [Member] | 3.75% To 8.75% Due April 2018 To July 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, interest rate		3.75%	3.75%
Maximum [Member] | 3.75% To 8.75% Due April 2018 To July 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, interest rate		8.75%	8.75%

[1] None of the Company’s long-term debt at September 30, 2016 and 2015 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.