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Postretirement benefits Schedule of Health Care Cost Trend Rates (Details) - Pension Plan [Member] - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
UNITED STATES |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Amortization of Prior Service Cost (Credit) | $ 0 | $ 0 | $ 0
Other changes in benefit plan assets and benefit obligations recognized in other comprehensive income, curtailment | $ 0 | $ 0 | $ 0
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract] |  |  |
Health Care Cost Trend Rate | 6.32% | 6.68% | 7.01%
Ultimate Health Care Cost Trend Rate | 4.50% | 4.50% | 4.50%
Year that Rate Reaches Ultimate Trend Rate | 2038 | 2038 | 2038
Non - U.S. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Amortization of Prior Service Cost (Credit) | $ 0 | $ 0 | $ 0
Other changes in benefit plan assets and benefit obligations recognized in other comprehensive income, curtailment | $ 3 | $ 0 | $ 6
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract] |  |  |
Health Care Cost Trend Rate | 5.24% | 6.29% | 6.61%
Ultimate Health Care Cost Trend Rate | 4.00% | 4.50% | 4.50%
Year that Rate Reaches Ultimate Trend Rate | 2040 | 2029 | 2029

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- Definition Amount before tax of gain (loss) adjustment to other comprehensive income (loss) resulting from curtailment of defined benefit pension and other postretirement defined benefit plans. + References No definition available. + Details
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(5) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(5) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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