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Retirement Benefits (Reconciliation of Net Actuarial Loss) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Pension Benefits |  |  |
Recognized as component of net periodic benefit cost (credit): |  |  |
Total recognized as component of net periodic benefit cost (credit) | $ (209) | $ (240) | $ (222)
Post-retirement Benefits |  |  |
Recognized as component of net periodic benefit cost (credit): |  |  |
Total recognized as component of net periodic benefit cost (credit) | 2 | 2 | 1
Net actuarial losses |  |  |
Recognized as component of net periodic benefit cost (credit): |  |  |
Amortization of net loss | 150 | 208 | 161
U.S. | Net actuarial losses | Pension Benefits |  |  |
Reconciliation of unrecognized net actuarial gain loss [Roll Forward] |  |  |
Beginning balance | (1,777) | (2,446) |
Recognized as component of net periodic benefit cost (credit): |  |  |
Amortization of net loss | 74 | 90 |
Liability experience | 1,625 | 227 |
Asset experience | (1,341) | 353 |
Other | 0 | (1) |
Total amount recognized as change in plan assets and benefit obligations | 284 | 579 |
Ending balance | (1,419) | (1,777) | (2,446)
U.S. | Net actuarial losses | Post-retirement Benefits |  |  |
Reconciliation of unrecognized net actuarial gain loss [Roll Forward] |  |  |
Beginning balance | 3 | 3 |
Recognized as component of net periodic benefit cost (credit): |  |  |
Amortization of net loss | 0 | (1) |
Liability experience | 3 | 1 |
Asset experience | 0 | 0 |
Other | 2 | 0 |
Total amount recognized as change in plan assets and benefit obligations | 5 | 1 |
Ending balance | 8 | 3 | 3
Non-U.S. | Pension Benefits |  |  |
Recognized as component of net periodic benefit cost (credit): |  |  |
Total recognized as component of net periodic benefit cost (credit) | (140) | (187) | (162)
Non-U.S. | Post-retirement Benefits |  |  |
Recognized as component of net periodic benefit cost (credit): |  |  |
Total recognized as component of net periodic benefit cost (credit) | 1 | 2 | 0
Non-U.S. | Net actuarial losses | Pension Benefits |  |  |
Reconciliation of unrecognized net actuarial gain loss [Roll Forward] |  |  |
Beginning balance | (2,904) | (3,467) |
Recognized as component of net periodic benefit cost (credit): |  |  |
Amortization of net loss | 75 | 116 |
Effect of settlement | 2 | 5 |
Total recognized as component of net periodic benefit cost (credit) | 77 | 121 |
Liability experience | 3,953 | 617 |
Asset experience | (4,051) | (199) |
Effect of curtailment | 0 | 2 |
Total amount recognized as change in plan assets and benefit obligations | (98) | 420 |
Exchange rate adjustments | 315 | 22 |
Ending balance | (2,610) | (2,904) | (3,467)
Non-U.S. | Net actuarial losses | Post-retirement Benefits |  |  |
Reconciliation of unrecognized net actuarial gain loss [Roll Forward] |  |  |
Beginning balance | (10) | (16) |
Recognized as component of net periodic benefit cost (credit): |  |  |
Amortization of net loss | 1 | 2 |
Effect of settlement | 0 | 0 |
Total recognized as component of net periodic benefit cost (credit) | 1 | 2 |
Liability experience | 14 | 4 |
Asset experience | 0 | 0 |
Effect of curtailment | 0 | 0 |
Total amount recognized as change in plan assets and benefit obligations | 14 | 4 |
Exchange rate adjustments | 1 | 0 |
Ending balance | $ 6 | $ (10) | $ (16)

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