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Accumulated Other Comprehensive Loss (Tables) | 12 Months Ended
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Dec. 31, 2024
Accumulated Other Comprehensive Loss [Abstract] |
Reclassification out of Accumulated Other Comprehensive Loss | The following table details the reclassifications out of accumulated other comprehensive loss by component for the years ended December 31 (dollars in millions):
|  | Amounts Reclassified from Accumulated Other Comprehensive Loss |
Details about Accumulated Other Comprehensive Loss Components (Affected Line Item in Statements of Income) |  | 2024 |  |  | 2023 |  |  | 2022 |
Amortization of defined benefit pension and postretirement benefit items |  |  |  |  |  |  |  |  |
Amortization of net prior service cost (a) |  | $ | 1 |  |  | $ | (1 | ) |  | $ | (4 | )
Amortization of net loss (a) |  |  | (12 | ) |  |  | 19 |  |  |  | 57 |
Adjustment due to effects of regulation (a) |  |  | 11 |  |  |  | (16 | ) |  |  | (42 | )
Total before tax (b) |  |  | — |  |  |  | 2 |  |  |  | 11 |
Tax expense (b) |  |  | — |  |  |  | — |  |  |  | (2 | )
Net of tax (b) |  | $ | — |  |  | $ | 2 |  |  | $ | 9 |
(a) These accumulated other comprehensive loss components are included in the computation of net periodic pension cost (see Note 12 for additional details). (b) Description is also the affected line item on the Consolidated Statements of Income.

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- Definition Accumulated Other Comprehensive Loss [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss). + References No definition available. + Details
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