Retirement Plan And Other Post-Retirement Benefits (Tables)

9 Months Ended

Jun. 30, 2024

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost (Income)

Components of Net Periodic Benefit Cost (in thousands):

	Retirement Plan				Other Post-Retirement Benefits
Three Months Ended June 30,	2024		2023		2024		2023
Service Cost	$	1,049	$	1,297	$	109	$	147
Interest Cost	10,890		10,629		3,890		3,912
Expected Return on Plan Assets	(17,086)		(16,648)		(6,660)		(6,403)
Amortization of Prior Service Cost (Credit)	91		109		(107)		(107)
Amortization of (Gains) Losses	(335)		(1,920)		(567)		(2,189)
Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	4,057		5,378		2,248		3,829
Net Periodic Benefit Cost (Income)	$	(1,334)	$	(1,155)	$	(1,087)	$	(811)

	Retirement Plan				Other Post-Retirement Benefits
Nine Months Ended June 30,	2024		2023		2024		2023
Service Cost	$	3,148	$	3,891	$	326	$	440
Interest Cost	32,668		31,887		11,671		11,736
Expected Return on Plan Assets	(51,257)		(49,945)		(19,981)		(19,210)
Amortization of Prior Service Cost (Credit)	271		327		(322)		(321)
Amortization of (Gains) Losses	(1,004)		(5,760)		(1,700)		(6,566)
Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	12,173		16,134		6,256		11,143
Net Periodic Benefit Cost (Income)	$	(4,001)	$	(3,466)	$	(3,750)	$	(2,778)

(1)The Company’s policy is to record retirement plan and other post-retirement benefit costs in the Utility segment on a volumetric basis to reflect the fact that the Utility segment experiences higher throughput of natural gas in the winter months and lower throughput of natural gas in the summer months.