Other Liabilities (Schedule of Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Other Liabilities [Line Items]
Accrued environmental remediation costs	$ 367	$ 362
Miscellaneous	1,222	1,581
Total other liabilities	12,591	13,615
Pension Plan [Member]
Other Liabilities [Line Items]
Accrued benefit costs (Note 18)	8,478	9,017
Other Long-Term Employee Benefit Plans [Member]
Other Liabilities [Line Items]
Accrued benefit costs (Note 18)	$ 2,524	$ 2,655