Financial Instruments (Tables)

12 Months Ended

Sep. 30, 2021

Financial Instruments, Owned, at Fair Value [Abstract]

Long-Term Debt

Based on these criteria, the fair market value of long-term debt, including current portion, was as follows:

	At September 30
	2021 Carrying Amount		2021  Fair Value		2020 Carrying Amount		2020  Fair Value
	(Thousands)
Long-Term Debt	$	2,628,687	$	2,898,552	$	2,629,576	$	2,778,556

Schedule of Other Investments

The components of the Company's Other Investments are as follows (in thousands):

	At September 30
	2021		2020
	(Thousands)
Life Insurance Contracts	$	44,560	$	41,992
Equity Mutual Fund	34,433		39,618
Fixed Income Mutual Fund	70,639		72,253
Marketable Equity Securities	—		639
	$	149,632	$	154,502

Schedule Of Derivative Financial Instruments Designated And Qualifying As Cash Flow Hedges On The Statements Of Financial Performance

The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the Year Ended September 30, 2021 and 2020 (Dollar Amounts in Thousands)
Derivatives in Cash Flow Hedging Relationships	Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) for the Year Ended September 30,				Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income	Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income for the Year Ended September 30,
	2021		2020			2021		2020
Commodity Contracts	$	(668,074)	$	9,905	Operating Revenue	$	(83,973)	$	93,691
Commodity Contracts	—		391		Purchased Gas	—		661
Foreign Currency Contracts	2,703		(434)		Operating Revenue	262		(1,057)
Total	$	(665,371)	$	9,862		$	(83,711)	$	93,295