XML 42 R32.htm IDEA: XBRL DOCUMENT v3.25.1
Interim Pension and Other Postretirement Benefit Plan Information (Tables)
 6 Months Ended
Mar. 31, 2025
Retirement Benefits, Description [Abstract]  
Schedule of Net Benefit Costs
 Three Months Ended March 31
 Pension BenefitsOther Benefits
 2025202420252024
 (In thousands)
Components of net periodic pension cost:
Service cost$2,837 $2,405 $2,033 $1,507 
Interest cost (1)
6,663 7,430 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 97 (2,429)(2,718)
Net periodic pension cost$2,101 $2,730 $(4,122)$(4,090)
 Six Months Ended March 31
 Pension BenefitsOther Benefits
2025202420252024
 (In thousands)
Components of net periodic pension cost:
Service cost$5,674 $4,794 $4,066 $3,014 
Interest cost (1)
13,326 14,926 6,731 7,017 
Expected return on assets (1)
(15,309)(14,404)(7,663)(6,256)
Amortization of prior service cost (credit) (1)
— — (6,520)(6,520)
Amortization of actuarial (gain) loss (1)
511 215 (4,858)(5,436)
Settlements (1)
— 776 — — 
Net periodic pension cost$4,202 $6,307 $(8,244)$(8,181)
(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.