CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash Flows From Operating Activities
Net income (loss)	$ 291,560	$ 266,104
Depreciation and amortization:
Charged to depreciation and amortization	204,059	185,731
Charged to other accounts	853	669
Other
Deferred income taxes	164,627	150,457
Other	18,146	21,587
Net Assets Liabilities From Risk Management Activities	(13,136)	3,158
Net change in operating assets and liabilities	51,473	2,504
Net cash provided by operating activities	717,582	630,210
Cash Flows From Investing Activities
Capital expenditures	(667,483)	(552,600)
Other, net	(1,119)	(620)
Net cash used in investing activities	(668,602)	(553,220)
Cash Flows From Financing Activities
Net decrease in short-term debt	48,830	(366,602)
Net proceeds from equity offering	0	390,205
Net proceeds from issuance of long-term debt	493,538	0
Settlement of interest rate agreements	13,364	0
Repayments of long-term debt	(500,000)	0
Cash dividends paid	(116,645)	(108,806)
Repurchase of equity awards	(7,985)	(8,717)
Issuance of common stock	20,813	2,152
Net cash provided by (used in) financing activities	(48,085)	(91,768)
Net increase (decrease) in cash and cash equivalents	895	(14,778)
Cash and cash equivalents at beginning of period	42,258	66,199
Cash and cash equivalents at end of period	$ 43,153	$ 51,421