Commitments and Contingencies (Details 1) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Amounts accrued for probable environmental remediation costs	$ 410	$ 385
Recorded Third-Party Environmental Recoveries, Amount	207	195
Financial Arrangements (Amounts in Paragraph)
Unused standby letters of credit and bank guarantees	186
Surety Bond Outstanding	197
Other Current Liabilities [Member]
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Amounts accrued for probable environmental remediation costs	148
Other Noncurrent Liabilities [Member]
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Amounts accrued for probable environmental remediation costs	262
Inventoried Costs [Member]
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Recorded Third-Party Environmental Recoveries, Amount	76
Other Noncurrent Assets [Member]
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Recorded Third-Party Environmental Recoveries, Amount	131
Maximum | Environmental Issue [Member]
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Loss Contingency, Estimate of Possible Loss	792	774
Minimum | Environmental Issue [Member]
Environmental Commitments and Contingencies (Amounts in Paragraphs)
Loss Contingency, Estimate of Possible Loss	$ 405	$ 379