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v3.25.2

Accumulated Other Comprehensive Income (Loss) (Changes in Accumulated Other Comprehensive Loss by Component) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Mar. 31, 2025 | Jun. 30, 2024 | Mar. 31, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |
Accumulated other comprehensive (income) loss, other, after tax, beginning balance |  |  | $ (1) |  | $ 1 | $ (1) | $ 1
Accumulated other comprehensive loss, beginning balance |  |  | (114) |  | (131) | (114) | (131)
Other comprehensive income (loss), before reclassifications, net of tax |  |  |  |  |  | 10 | (2)
Amounts reclassified from accumulated other comprehensive loss: |  |  |  |  |  |  |
Amortization of prior service credit |  |  |  |  |  | (15) | (27)
Amortization of actuarial loss |  |  |  |  |  | 8 | 2
Settlement loss |  |  |  |  |  | 1 |
Other |  |  |  |  |  | 1 |
Tax effect |  |  |  |  |  | 1 | 6
Other comprehensive income (loss) |  | $ 1 | 5 | $ (9) | (12) | 6 | (21)
Accumulated other comprehensive (income) loss, other, after tax, ending balance |  | 0 |  | (2) |  | 0 | (2)
Accumulated other comprehensive loss, ending balance |  | (108) |  | (152) |  | (108) | (152)
Other comprehensive income (loss) before reclassifications, tax |  |  |  |  |  | 3 | (1)
Pension Benefits |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |
Accumulated other comprehensive (income) loss, defined benefit plan, after tax, beginning balance |  |  | (235) |  | (261) | (235) | (261)
Amounts reclassified from accumulated other comprehensive loss: |  |  |  |  |  |  |
Accumulated other comprehensive (income) loss, defined benefit plan, after tax, ending balance |  | (224) |  | (270) |  | (224) | (270)
Other Benefits |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |
Accumulated other comprehensive (income) loss, defined benefit plan, after tax, beginning balance |  |  | $ 122 |  | $ 129 | 122 | 129
Amounts reclassified from accumulated other comprehensive loss: |  |  |  |  |  |  |
Accumulated other comprehensive (income) loss, defined benefit plan, after tax, ending balance |  | $ 116 |  | $ 120 |  | 116 | 120
Accumulated Defined Benefit Plans Adjustment | Pension Benefits |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |
Other comprehensive income (loss), before reclassifications, net of tax |  |  |  |  |  | 8 | 2
Amounts reclassified from accumulated other comprehensive loss: |  |  |  |  |  |  |
Amortization of prior service credit | [1] |  |  |  |  | (4) | (16)
Amortization of actuarial loss | [1] |  |  |  |  | 8 | 2
Settlement loss | [1] |  |  |  |  | 1 |
Tax effect |  |  |  |  |  | (2) | 3
Other comprehensive income (loss) |  |  |  |  |  | 11 | (9)
Accumulated Defined Benefit Plans Adjustment | Other Benefits |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |
Other comprehensive income (loss), before reclassifications, net of tax |  |  |  |  |  | 2 | (1)
Amounts reclassified from accumulated other comprehensive loss: |  |  |  |  |  |  |
Amortization of prior service credit | [1] |  |  |  |  | (11) | (11)
Amortization of actuarial loss | [1] |  |  |  |  | 0 | 0
Settlement loss |  |  |  |  |  | 0 |
Tax effect |  |  |  |  |  | 3 | 3
Other comprehensive income (loss) |  |  |  |  |  | (6) | (9)
Other |  |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |  |
Other comprehensive income (loss), before reclassifications, net of tax |  |  |  |  |  | 0 | (3)
Amounts reclassified from accumulated other comprehensive loss: |  |  |  |  |  |  |
Other |  |  |  |  |  | 1 |
Tax effect |  |  |  |  |  | 0 | 0
Other comprehensive income (loss) |  |  |  |  |  | $ 1 | $ (3)
[1] | These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost. See Note 21.

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