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Pension and Other Postretirement Benefit Plans - Components of Other Comprehensive Income (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Other Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net gain (loss) arising during the period | $ (78) | $ 110 | $ 0
Prior service credit (cost) arising during the period | 0 | 0 | 0
Total | (78) | 110 | 0
Net loss (gain) amortization included in benefit cost | (51) | (42) | (43)
Prior service (credit) cost amortization included in benefit cost | (43) | (49) | (57)
Settlements and curtailments | 0 | (1) | (1)
Total | (94) | (92) | (101)
United States | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net gain (loss) arising during the period | 35 | (69) | (42)
Prior service credit (cost) arising during the period | 0 | 0 | 0
Total | 35 | (69) | (42)
Net loss (gain) amortization included in benefit cost | 43 | 0 | 128
Prior service (credit) cost amortization included in benefit cost | 0 | (1) | (32)
Settlements and curtailments | 0 | 36 | 251
Total | 43 | 35 | 347
International | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net gain (loss) arising during the period | 634 | (438) | 116
Prior service credit (cost) arising during the period | 56 | (16) | (4)
Total | 690 | (454) | 112
Net loss (gain) amortization included in benefit cost | 5 | (3) | 96
Prior service (credit) cost amortization included in benefit cost | (13) | 2 | (14)
Settlements and curtailments | (1) | (6) | 1
Total | $ (9) | $ (7) | $ 83

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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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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 15 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-15 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 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 17A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-17A + Details
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