Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
OPERATING ACTIVITIES
Net Income (Loss) Available for Common Stock	$ (19,477)	$ 193,256
Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities:
Impairment of Oil and Gas Producing Properties	177,761	0
Depreciation, Depletion and Amortization	152,830	129,918
Deferred Income Taxes	104,883	90,468
Stock-Based Compensation	7,580	10,731
Other	9,800	7,997
Change in:
Receivables and Unbilled Revenue	(58,248)	(130,377)
Gas Stored Underground and Materials and Supplies	20,086	29,093
Unrecovered Purchased Gas Costs	2,246	(1,556)
Other Current Assets	(3,134)	10,438
Accounts Payable	(5,465)	10,226
Amounts Payable to Customers	13,196	12,069
Customer Advances	(12,429)	(13,176)
Customer Security Deposits	(1,211)	(7,184)
Other Accruals and Current Liabilities	9,076	48,028
Other Assets	(10,359)	(38,686)
Other Liabilities	3,857	(10,410)
Net Cash Provided by Operating Activities	390,992	340,835
INVESTING ACTIVITIES
Capital Expenditures	(395,486)	(386,579)
Other	4,167	(2,616)
Net Cash Used in Investing Activities	(391,319)	(389,195)
Financing Activities
Changes in Notes Payable to Banks and Commercial Paper	174,800	0
Dividends Paid on Common Stock	(75,197)	(73,197)
Net Repurchases of Common Stock	(4,153)	(8,864)
Net Cash Provided by (Used in) Financing Activities	95,450	(82,061)
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	95,123	(130,421)
Cash, Cash Equivalents and Restricted Cash at October 1	27,260	233,047
Cash, Cash Equivalents and Restricted Cash at March 31	122,383	102,626
Supplemental Disclosure of Cash Flow Information, Non-Cash Investing Activities:
Non-Cash Capital Expenditures	$ 59,490	$ 74,929