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Employee Benefits - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Pre-tax AOCI not yet recognized as net pension cost |  | $ 384 | $ 385 |
Accumulated benefit obligation for all pension plans |  | $ 922 | $ 965 |
Percentage increase or decrease in expected return on plan assets |  | 0.25% |  |
Estimated increase or decrease in net pension cost |  | $ 2 |  |
Percentage increase or decrease in assumed discount rate |  | 0.25% |  |
Estimated change in net pension cost due to discount rate |  | $ 2 |  |
Expected return on plan assets |  | 4.50% | 2.75% | 2.75%
Expected return on plan assets on estimating 2023 pension cost |  | 4.50% |  |
Employer contribution to saving plan |  | 7.00% |  |
Employer discretionary contribution, required service period |  | 1 year |  |
Employer discretionary contribution percentage |  |  |  | 1.00%
Total expenses associated with saving plan |  | $ 99 | $ 82 | $ 119
Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2024 |  | 89 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2025 |  | 87 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2026 |  | 84 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2027 |  | 81 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2028 |  | 79 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2029 through 2033 |  | 347 |  |
Accumulated benefit obligation for all pension plans |  | 793 | 828 |
Net periodic benefit cost (credit) |  | $ 30 | $ 27 | $ 24
Expected return on plan assets |  | 4.50% | 4.50% | 2.75%
Discount rate |  | 4.68% | 4.85% |
Other Postretirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Pre-tax AOCI not yet recognized as net pension cost |  | $ (20) | $ (21) |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2024 |  | 5 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2025 |  | 5 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2026 |  | 5 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2027 |  | 4 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2028 |  | 4 |  |
Benefits expected to be paid from all funded and unfunded pension plans/other postretirement plans in 2029 through 2033 |  | 19 |  |
Net periodic benefit cost (credit) |  | $ (2) | $ (2) | $ (2)
Expected return on plan assets |  | 4.50% | 4.50% | 4.50%
Age of employees under condition one |  | 55 years |  |
Period of service under condition one |  | 5 years |  |
Age of employees under condition two |  | 50 years |  |
Period of service under condition two |  | 15 years |  |
Minimum period of service at the time of termination hired before 2001 |  | 15 years |  |
Discount rate |  | 4.50% | 4.50% |
Forecast | Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Net periodic benefit cost (credit) | $ 11 |  |  |
Forecast | Other Postretirement Benefit Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Net periodic benefit cost (credit) | $ 2 |  |  |
Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employees contribution to saving plan |  | 1.00% |  |
Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employees contribution to saving plan |  | 100.00% |  |

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