Goodwill and Intangible Assets (Goodwill Rollforward) (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Goodwill Roll Forward | ||
| Beginning Balance | $ 6,597 | $ 6,577 |
| Foreign currency and other | (21) | 20 |
| Acquired | 112 | |
| Ending Balance | 6,688 | 6,597 |
| Goodwill, Impaired, Accumulated Impairment Loss | ||
| Goodwill, accumulated impairments | 700 | 700 |
| IS | ||
| Goodwill Roll Forward | ||
| Beginning Balance | 295 | 275 |
| Foreign currency and other | (21) | 20 |
| Acquired | 0 | |
| Ending Balance | 274 | 295 |
| Goodwill, Impaired, Accumulated Impairment Loss | ||
| Goodwill, accumulated impairments | 673 | 673 |
| WM | ||
| Goodwill Roll Forward | ||
| Beginning Balance | 5,533 | 5,533 |
| Foreign currency and other | 0 | 0 |
| Acquired | 0 | |
| Ending Balance | 5,533 | 5,533 |
| Goodwill, Impaired, Accumulated Impairment Loss | ||
| Goodwill, accumulated impairments | 0 | 0 |
| IM | ||
| Goodwill Roll Forward | ||
| Beginning Balance | 769 | 769 |
| Foreign currency and other | 0 | 0 |
| Acquired | 112 | |
| Ending Balance | 881 | 769 |
| Goodwill, Impaired, Accumulated Impairment Loss | ||
| Goodwill, accumulated impairments | $ 27 | $ 27 |