Property, Plant And Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 1,910	$ 1,833	$ 1,906
Interest capitalized	170	158	102
Rental expense for leased properties	287	267	277
Minimum rental payments under capital leases, total	144
Minimum rental payments under operating leases with initial or remaining terms of one year or more, total	1,475
Sublease payments under operating lease	19
Property, plant and equipment included in accounts payable	292	502
Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 1,418	$ 1,357	$ 1,414