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Pension and Other Postretirement Benefit Plans - Components of Other Comprehensive Income (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Other Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net (loss) gain arising during the period | $ 110 | $ 0 | $ 156
Prior service cost arising during the period | 0 | 0 | 0
Total | 110 | 0 | 156
Net loss (gain) amortization included in benefit cost | (42) | (43) | (42)
Prior service (credit) cost amortization included in benefit cost | (49) | (57) | (63)
Settlements and curtailments | (1) | (1) | (29)
Total | (92) | (101) | (134)
United States | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net (loss) gain arising during the period | (69) | (42) | 813
Prior service cost arising during the period | 0 | 0 | 0
Total | (69) | (42) | 813
Net loss (gain) amortization included in benefit cost | 0 | 128 | 298
Prior service (credit) cost amortization included in benefit cost | (1) | (32) | (38)
Settlements and curtailments | 36 | 251 | 232
Total | 35 | 347 | 492
International | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net (loss) gain arising during the period | (438) | 116 | 772
Prior service cost arising during the period | (16) | (4) | (4)
Total | (454) | 112 | 768
Net loss (gain) amortization included in benefit cost | (3) | 96 | 142
Prior service (credit) cost amortization included in benefit cost | 2 | (14) | (16)
Settlements and curtailments | (6) | 1 | (18)
Total | $ (7) | $ 83 | $ 108

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- Definition Amount, before tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (j) -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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