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v3.25.1

Employee Benefit Plans (Notes) | 3 Months Ended
--- | ---
Mar. 31, 2025
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract] |
Pension and Other Postretirement Benefits Disclosure [Text Block] | 9. EMPLOYEE BENEFIT PLANS The components of net periodic benefit cost (credit) are as follows:
|  |  |  |  |  | Pension Benefits
|  |  |  | Three Months Ended
|  |  |  | March 31,
|  |  |  |  |  | 2025 |  | 2024
|  |  |  |  |  | (in millions)
Service cost |  |  |  |  |  | $ | 0.1 |  |  | $ | 0.3 |
Interest cost |  |  |  |  |  | 6.0 |  |  | 5.8 |
Expected asset return |  |  |  |  |  | (6.4) |  |  | (7.2) |
Amortized loss |  |  |  |  |  | 2.1 |  |  | 1.7 |
Net periodic benefit cost |  |  |  |  |  | $ | 1.8 |  |  | $ | 0.6 |
|  |  |  |  |  | Other Postretirement Benefits
|  |  |  | Three Months Ended
|  |  |  | March 31,
|  |  |  |  |  | 2025 |  | 2024
|  |  |  |  |  | (in millions)
Service cost |  |  |  |  |  | $ | — |  |  | $ | — |
Interest cost |  |  |  |  |  | 2.3 |  |  | 2.1 |
Amortized gain |  |  |  |  |  | (2.3) |  |  | (2.5) |
Amortized prior service credit |  |  |  |  |  | (0.2) |  |  | (0.1) |
Net periodic benefit credit |  |  |  |  |  | $ | (0.2) |  |  | $ | (0.5) |
The noncurrent liabilities associated with our pension and other postretirement benefit plans are classified as Postretirement benefits and other long-term liabilities on our Condensed Consolidated Balance Sheets. As of March 31, 2025 and December 31, 2024, we have a noncurrent pension liability of $78.4 million and $78.3 million, respectively. As of March 31, 2025 and December 31, 2024, we have a noncurrent other postretirement benefits liability of $265.6 million and $265.3 million, respectively. Due to the availability of our pre-funded pension balances (previous contributions in excess of prior required pension contributions), we expect our regulatory pension funding requirements in 2025 to be approximately $1.1 million. We expect our cash payments for other postretirement benefit obligations in 2025, net of GM cost sharing, to be approximately $11.6 million.

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