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Postretirement benefits Schedule of Benefit Obligation in Excess of FV (Details) - Pension Plan [Member] - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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UNITED STATES |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation | $ 3,092 | $ 3,285
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets | 2,784 | 3,109
Net Funded Status With PBO in Excess Of Plan Assets | (308) | (176)
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation | 3,066 | 3,223
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets | 2,784 | 3,109
Non-US [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation | 222 | 216
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets | 170 | 166
Net Funded Status With PBO in Excess Of Plan Assets | (52) | (50)
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation | 115 | 152
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets | $ 86 | $ 123

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- Definition Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920 + Details
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- Definition Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920 + Details
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