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 |