Pension and Other Postretirement Benefit Plans (Expected Benefit Payments) (Details) $ in Millions	Dec. 31, 2017 USD ($)
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2018	$ 41
2019	43
2020	33
2021	32
2022	31
2023-2027	130
United States Pension Benefits \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2018	298
2019	271
2020	260
2021	259
2022	250
2023-2027	1,120
Foreign Pension Benefits \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2018	42
2019	42
2020	40
2021	41
2022	42
2023-2027	$ 219

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

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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