Supplemental Balance Sheet Information - PP&E (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Property, plant and equipment - at cost
Gross property, plant and equipment	$ 24,873	$ 24,914
Less: Accumulated depreciation	(16,135)	(16,048)
Property, Plant and Equipment - net	8,738	8,866
Accumulated depreciation for capital leases included in Accumulated depreciation	54	48
Land
Property, plant and equipment - at cost
Gross property, plant and equipment	340	348
Buildings and leasehold improvements
Property, plant and equipment - at cost
Gross property, plant and equipment	7,517	7,681
Machinery and equipment
Property, plant and equipment - at cost
Gross property, plant and equipment	15,680	15,907
Construction in progress
Property, plant and equipment - at cost
Gross property, plant and equipment	1,193	843
Capital leases
Property, plant and equipment - at cost
Gross property, plant and equipment	$ 143	$ 135

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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