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Retirement Benefits (Reconciliation of Prior Service Credit) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Pension Benefits |  |  |
Recognized as component of net periodic benefit credit: |  |  |
Total recognized as component of net periodic benefit credit | $ (222) | $ (234) | $ (181)
Post-retirement Benefits |  |  |
Recognized as component of net periodic benefit credit: |  |  |
Total recognized as component of net periodic benefit credit | 1 | 0 | 1
Non-U.S. | Pension Benefits |  |  |
Recognized as component of net periodic benefit credit: |  |  |
Total recognized as component of net periodic benefit credit | (162) | (176) | (114)
Non-U.S. | Post-retirement Benefits |  |  |
Recognized as component of net periodic benefit credit: |  |  |
Total recognized as component of net periodic benefit credit | 0 | 0 | 1
Non-U.S. | Prior Service Credit (Cost) | Pension Benefits |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | (2) | (2) |
Recognized as component of net periodic benefit credit: |  |  |
Amortization of prior service credit | 0 | 0 |
Total recognized as component of net periodic benefit credit | 0 | 0 |
Plan amendments | (11) | 1 |
Exchange rate adjustments | 0 | (1) |
Ending balance | (13) | (2) | (2)
Non-U.S. | Prior Service Credit (Cost) | Post-retirement Benefits |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | 11 | 12 |
Recognized as component of net periodic benefit credit: |  |  |
Amortization of prior service credit | (2) | (2) |
Total recognized as component of net periodic benefit credit | (2) | (2) |
Plan amendments | 0 | 0 |
Exchange rate adjustments | 0 | 1 |
Ending balance | $ 9 | $ 11 | $ 12

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- Definition Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, including portion attributable to noncontrolling interest. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners). + References No definition available. + Details
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