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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Contribution Plan, Cost |  | $ 46 | $ 88 | $ 95
Pension Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | 9,298 | 12,182 | $ 12,873
Pension Benefits | UNITED STATES |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | $ 8,425 | $ 11,086 |
Weighted average expected return on plan assets |  | 5.00% | 5.00% | 5.50%
Pension Benefits | Non- U.S. Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | $ 873 | $ 1,096 |
Pension Benefits | Scenario, Forecast | UNITED STATES |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Weighted average expected return on plan assets | 6.25% |  |  |
Other Postretirement Benefits |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | 794 | 1,138 | $ 1,252
Other Postretirement Benefits | UNITED STATES |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | $ 758 | $ 1,099 |
Weighted average expected return on plan assets |  | 3.86% | 3.87% | 4.31%
Expected future discretionary contributions |  | $ 20 |  |
Other Postretirement Benefits | Non- U.S. Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | 36 | $ 39 |
Other Postretirement Benefits | Scenario, Forecast | UNITED STATES |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Weighted average expected return on plan assets | 4.25% |  |  |
United States Pension Plan of US Entity, Non Qualified [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Aggregate projected benefit obligations |  | 1,000 | $ 1,300 |
Expected future discretionary contributions |  | $ 90 |  |

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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 8 -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920 + Details
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