Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
OPERATING ACTIVITIES
Net Income Available for Common Stock	$ 86,591	$ 102,660
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Depreciation, Depletion and Amortization	74,918	64,255
Deferred Income Taxes	51,366	64,175
Stock-Based Compensation	3,266	5,311
Other	1,911	2,182
Change in:
Receivables and Unbilled Revenue	(58,655)	(101,541)
Gas Stored Underground and Materials and Supplies	6,985	8,353
Unrecovered Purchased Gas Costs	627	(4,496)
Other Current Assets	14	(1,195)
Accounts Payable	8,280	1,502
Amounts Payable to Customers	(573)	(3,394)
Customer Advances	683	(6,258)
Customer Security Deposits	(700)	(1,861)
Other Accruals and Current Liabilities	15,438	38,412
Other Assets	(28,259)	(42,400)
Other Liabilities	5,857	(21,333)
Net Cash Provided by Operating Activities	167,749	104,372
INVESTING ACTIVITIES
Capital Expenditures	(198,495)	(177,567)
Other	5,212	(2,549)
Net Cash Used in Investing Activities	(193,283)	(180,116)
Financing Activities
Changes in Notes Payable to Banks and Commercial Paper	84,600	0
Dividends Paid on Common Stock	(37,547)	(36,532)
Net Repurchases of Common Stock	(4,147)	(8,233)
Net Cash Provided by (Used in) Financing Activities	42,906	(44,765)
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	17,372	(120,509)
Cash, Cash Equivalents and Restricted Cash at October 1	27,260	233,047
Cash, Cash Equivalents and Restricted Cash at December 31	44,632	112,538
Supplemental Disclosure of Cash Flow Information, Non-Cash Investing Activities:
Non-Cash Capital Expenditures	$ 93,838	$ 86,175