Income Taxes (Components Of Federal And State Income Taxes Included In The Consolidated Statements Of Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Current Income Taxes [Abstract]
Federal	$ (8,227)	$ 16,528
State	3,890	5,425
Deferred Income Taxes [Abstract]
Federal	(97,705)	26,193
State	(42,308)	7,014
Income Tax Expense (Benefit)	(144,350)	55,160
Deferred Investment Tax Credit	(87)	(104)
Total Income Taxes	(144,437)	55,056
Presented as Follows [Abstract]
Other Income	(87)	(104)
Income Tax Expense (Benefit)	$ (144,350)	$ 55,160