Consolidated Statements Of Income And Earnings Reinvested In The Business (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
INCOME
Operating Revenues	$ 328,861	$ 380,979	$ 1,313,593	$ 1,492,808
Operating Expenses
Purchased Gas	50,160	112,725	390,889	582,358
Operation and Maintenance	93,749	95,977	311,857	310,148
Property, Franchise and Other Taxes	20,432	20,179	70,138	63,714
Depreciation, Depletion and Amortization	74,227	57,293	199,925	170,617
Total Operating Expenses	238,568	286,174	972,809	1,126,837
Operating Income	90,293	94,805	340,784	365,971
Other Income (Expense):
Gain on Sale of Unconsolidated Subsidiaries			0	50,879
Interest Income	390	325	1,686	1,277
Other Income	1,086	1,813	4,076	4,130
Interest Expense on Long-Term Debt	(21,529)	(17,876)	(60,594)	(55,994)
Other Interest Expense	(828)	(1,159)	(2,851)	(4,014)
Income Before Income Taxes	69,412	77,908	283,101	362,249
Income Tax Expense	26,228	31,017	111,826	141,204
Net Income Available for Common Stock	43,184	46,891	171,275	221,045
EARNINGS REINVESTED IN THE BUSINESS
Beginning Balance	1,275,107	1,180,531	1,206,022	1,063,262
Beginning Retained Earnings Unappropriated And Current Period Net Income Loss	1,318,291	1,227,422	1,377,297	1,284,307
Dividends on Common Stock	(30,393)	(29,358)	(89,399)	(86,243)
Balance at June 30	$ 1,287,898	$ 1,198,064	$ 1,287,898	$ 1,198,064
Earnings Per Common Share, Basic:
Net Income Available for Common Stock	$ 0.52	$ 0.57	$ 2.06	$ 2.68
Diluted:
Net Income Available for Common Stock	$ 0.52	$ 0.56	$ 2.05	$ 2.64
Weighted Average Common Shares Outstanding:
Used in Basic Calculation	83,227,602	82,687,467	83,068,083	82,436,603
Used in Diluted Calculation	83,674,823	83,782,493	83,690,436	83,649,498