Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
OPERATING ACTIVITIES
Net Income Available for Common Stock	$ 299,720	$ 190,210
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Gain on Sale of Timber Properties	0	(51,066)
Impairment of Oil and Gas Producing Properties	0	76,152
Depreciation, Depletion and Amortization	179,823	167,462
Deferred Income Taxes	94,212	61,408
Premium Paid on Early Redemption of Debt	0	15,715
Stock-Based Compensation	10,631	8,657
Reduction of Other Post-Retirement Regulatory Liability	(18,533)	0
Other	14,494	6,742
Change in:
Receivables and Unbilled Revenue	(166,584)	(101,159)
Gas Stored Underground and Materials, Supplies and Emission Allowances	32,040	27,258
Unrecovered Purchased Gas Costs	29,377	(479)
Other Current Assets	(8,605)	(8,447)
Accounts Payable	2,006	8,613
Amounts Payable to Customers	3,401	8,980
Customer Advances	(17,223)	(15,319)
Customer Security Deposits	1,474	2,304
Other Accruals and Current Liabilities	11,164	9,058
Other Assets	(32,659)	11,039
Other Liabilities	(9,119)	5
Net Cash Provided by Operating Activities	425,619	417,133
INVESTING ACTIVITIES
Capital Expenditures	(415,415)	(338,867)
Net Proceeds from Sale of Oil and Gas Producing Properties	13,525	0
Net Proceeds from Sale of Timber Properties	0	104,582
Sale of Fixed Income Mutual Fund Shares in Grantor Trust	30,000	0
Other	13,689	12,095
Net Cash Used in Investing Activities	(358,201)	(222,190)
Financing Activities
Changes in Notes Payable to Banks and Commercial Paper	59,500	(30,000)
Net Proceeds from Issuance of Long-Term Debt	0	495,267
Reduction of Long-term Debt	0	(515,715)
Dividends Paid on Common Stock	(83,091)	(81,035)
Net Repurchases of Common Stock	(9,026)	(3,534)
Net Cash Used in Financing Activities	(32,617)	(135,017)
Net Increase in Cash, Cash Equivalents, and Restricted Cash	34,801	59,926
Cash, Cash Equivalents and Restricted Cash at October 1	120,138	20,541
Cash, Cash Equivalents and Restricted Cash at March 31	154,939	80,467
Supplemental Disclosure of Cash Flow Information, Non-Cash Investing Activities:
Non-Cash Capital Expenditures	$ 63,490	$ 68,073