Retirement Plan And Other Post-Retirement Benefits (Tables)

9 Months Ended

Jun. 30, 2020

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost

Components of Net Periodic Benefit Cost (in thousands):

	Retirement Plan				Other Post-Retirement Benefits
Three Months Ended June 30,	2020		2019		2020		2019
Service Cost	$	2,330	$	2,120	$	402	$	380
Interest Cost	7,483		9,594		3,228		4,286
Expected Return on Plan Assets	(15,016)		(15,591)		(7,308)		(7,539)
Amortization of Prior Service Cost (Credit)	182		206		(107)		(107)
Amortization of Losses	9,846		8,024		134		1,490
Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	604		(113)		6,036		3,757
Net Periodic Benefit Cost	$	5,429	$	4,240	$	2,385	$	2,267

	Retirement Plan				Other Post-Retirement Benefits
Nine Months Ended June 30,	2020		2019		2020		2019
Service Cost	$	6,989	$	6,362	$	1,206	$	1,140
Interest Cost	22,448		28,783		9,685		12,858
Expected Return on Plan Assets	(45,048)		(46,775)		(21,924)		(22,618)
Amortization of Prior Service Cost (Credit)	547		619		(322)		(321)
Amortization of Losses	29,538		24,072		401		4,471
Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	7,651		5,490		21,131		14,294
Net Periodic Benefit Cost	$	22,125	$	18,551	$	10,177	$	9,824

⁽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.