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Postretirement benefits Schedule of net periodic benefit costs (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | $ 7 | $ 4 | $ 4
Defined Benefit Plan, Non Service (Benefit) Cost | (94) | (218) | (203)
Net Periodic Benefit Cost | (87) | (214) | (199)
Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 0 | 1 | 1
Interest Cost | 2 | 1 | 1
Expected Return on Plan Assets | (3) | (1) | (1)
Amortization of (Gains) Losses | (1) | 0 | 0
Amortization of Prior Service Cost (Credit) | 0 | 0 | (26)
Recognized Net (Gain) Loss Due to Curtailments | 0 | 0 | 0
Recognized Net (Gain) Loss Due to Settlements | 0 | 0 | 0
Defined Benefit Plan, Non Service (Benefit) Cost | (2) | 0 | (26)
Net Periodic Benefit Cost | (2) | 1 | (25)
(Increase) decrease in Other Comprehensive Income (Loss), Net Actuarial (Gain) Loss) | 2 | (1) | (5)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax | 0 | 0 | 0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax | 1 | 0 | 0
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax | 0 | 0 | 26
(Increase) decrease in other comprehensive income, curtailment | 0 | 0 | 0
(Increase) decrease in other comprehensive income, settlement | 0 | 0 | 0
Total (increase) decrease in other comprehensive (Income) Loss | 3 | (1) | 21
Losses and loss expenses [Member] | Pension Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 0 | 0 | 0
Defined Benefit Plan, Non Service (Benefit) Cost | (9) | (20) | (18)
Losses and loss expenses [Member] | Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 0 | 0 | 0
Defined Benefit Plan, Non Service (Benefit) Cost | 0 | 0 | (3)
General and Administrative Expense [Member] | Pension Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 7 | 4 | 4
Defined Benefit Plan, Non Service (Benefit) Cost | (85) | (198) | (185)
General and Administrative Expense [Member] | Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 0 | 1 | 1
Defined Benefit Plan, Non Service (Benefit) Cost | (2) | 0 | (23)
UNITED STATES | Pension Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 0 | 0 | 0
Interest Cost | 138 | 85 | 70
Expected Return on Plan Assets | (225) | (283) | (255)
Amortization of (Gains) Losses | 0 | 0 | 0
Amortization of Prior Service Cost (Credit) | 0 | 0 | 0
Recognized Net (Gain) Loss Due to Curtailments | 0 | 0 | 0
Recognized Net (Gain) Loss Due to Settlements | 3 | 0 | 3
Defined Benefit Plan, Non Service (Benefit) Cost | (84) | (198) | (182)
Net Periodic Benefit Cost | (84) | (198) | (182)
(Increase) decrease in Other Comprehensive Income (Loss), Net Actuarial (Gain) Loss) | (111) | 85 | (450)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax | 0 | 0 | 0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax | 0 | 0 | 0
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax | 0 | 0 | 0
(Increase) decrease in other comprehensive income, curtailment | 0 | 0 | 0
(Increase) decrease in other comprehensive income, settlement | (3) | 0 | (3)
Total (increase) decrease in other comprehensive (Income) Loss | (114) | 85 | (453)
Non - U.S. | Pension Plan [Member] |  |  |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax [Abstract] |  |  |
Service Cost | 7 | 4 | 4
Interest Cost | 36 | 23 | 19
Expected Return on Plan Assets | (51) | (43) | (44)
Amortization of (Gains) Losses | 0 | 0 | 4
Amortization of Prior Service Cost (Credit) | 1 | 0 | 0
Recognized Net (Gain) Loss Due to Curtailments | 0 | 0 | 0
Recognized Net (Gain) Loss Due to Settlements | 4 | 0 | 0
Defined Benefit Plan, Non Service (Benefit) Cost | (10) | (20) | (21)
Net Periodic Benefit Cost | (3) | (16) | (17)
(Increase) decrease in Other Comprehensive Income (Loss), Net Actuarial (Gain) Loss) | 22 | (67) | (86)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax | 0 | 0 | 0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax | 0 | 0 | (4)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax | 0 | 0 | 0
(Increase) decrease in other comprehensive income, curtailment | 0 | 0 | 0
(Increase) decrease in other comprehensive income, settlement | (1) | 0 | 0
Total (increase) decrease in other comprehensive (Income) Loss | $ 21 | $ (67) | $ (90)

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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(7) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(7) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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