Pensions And Other Postretirement Benefits Pension Benefit Payments (Details) $ in Millions	Dec. 31, 2017 USD ($)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payments [Abstract]
2018	$ 379
2019	374
2020	368
2021	365
2022	362
2023 - 2027	1,817
U.S. [Member] \| Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payments [Abstract]
2018	5,288
2019	5,053
2020	4,895
2021	4,758
2022	4,639
2023 - 2027	21,553
Non-U.S. [Member] \| Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payments [Abstract]
2018	1,458
2019	1,323
2020	1,302
2021	1,276
2022	1,233
2023 - 2027	$ 5,759

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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