Interim Pension and Other Postretirement Benefit Plan Information (Tables)

3 Months Ended

Dec. 31, 2024

Retirement Benefits, Description [Abstract]

Schedule of Net Benefit Costs

	Three Months Ended December 31
	Pension Benefits				Other Benefits
	2024		2023		2024		2023
	(In thousands)
Components of net periodic pension cost:
Service cost	$	2,837	$	2,389	$	2,033	$	1,507
Interest cost (1)	6,663		7,497		3,365		3,509
Expected return on assets (1)	(7,655)		(7,202)		(3,831)		(3,128)
Amortization of prior service cost (credit) (1)	—		—		(3,260)		(3,260)
Amortization of actuarial (gain) loss (1)	256		118		(2,429)		(2,718)
Settlements (1)	—		776		—		—
Net periodic pension cost	$	2,101	$	3,578	$	(4,122)	$	(4,090)

(1)    The components of net periodic cost other than the service cost component are included in the line item other non-operating expense in the condensed consolidated statements of comprehensive income or are capitalized on the condensed consolidated balance sheets as a regulatory asset or liability, as described in Note 2 to the consolidated financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2024.