CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash Flows From Operating Activities
Net income	$ 629,531	$ 574,208
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	294,337	261,230
Deferred income taxes	59,060	40,122
Other	(27,496)	(12,812)
Net assets / liabilities from risk management activities	(1,482)	(4,172)
Net change in Winter Storm Uri current regulatory asset (See Note 8)	2,021,889	0
Net change in other operating assets and liabilities	(83,123)	(218,092)
Net cash provided by operating activities	2,892,716	640,484
Cash Flows From Investing Activities
Capital expenditures	(1,415,349)	(1,190,029)
Debt and equity securities activities, net	(4,560)	3,758
Other, net	9,519	4,302
Net cash used in investing activities	(1,410,390)	(1,181,969)
Cash Flows From Financing Activities
Net decrease in short-term debt	(184,967)	0
Net proceeds from equity issuances	359,683	594,320
Issuance of common stock through stock purchase and employee retirement plans	7,910	8,010
Proceeds from issuance of long-term debt	797,258	798,802
Proceeds from term loan	2,020,000	0
Repayment of term loan	(2,020,000)	0
Repayment of long-term debt	(2,200,000)	(200,000)
Cash dividends paid	(210,725)	(183,944)
Debt issuance costs	(7,864)	(8,196)
Other	0	(1,735)
Net cash provided by (used in) financing activities	(1,438,705)	1,007,257
Net increase in cash and cash equivalents	43,621	465,772
Cash and cash equivalents at beginning of period	51,554	116,723
Cash and cash equivalents at end of period	$ 95,175	$ 582,495