Significant Accounting Policies (Property) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ (6,444)	$ (6,190)
Property plant and equipment, net	3,301	3,414
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	97	102
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 1,540	1,593
Buildings | Minimum
Property, Plant and Equipment [Line Items]
Property, plan, and equipment, useful life	10 years
Buildings | Maximum
Property, Plant and Equipment [Line Items]
Property, plan, and equipment, useful life	50 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 8,108	$ 7,909
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plan, and equipment, useful life	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plan, and equipment, useful life	20 years