(Schedule of Unrecognized Tax Benefits Rollforward) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Income Tax Disclosure [Abstract] | |||
| Balance at January 1 | $ (220) | $ (188) | $ (98) |
| (Additions) reductions for tax positions related to current year | (5) | (7) | (54) |
| (Additions) for tax positions related to prior years | (6) | (37) | (40) |
| Reductions for tax positions related to prior years | 5 | 5 | 4 |
| Settlements | 31 | 2 | 6 |
| Expiration of statutes of limitations | 3 | 2 | 1 |
| Currency translation adjustment | 3 | 3 | (7) |
| Balance at December 31 | $ (189) | $ (220) | $ (188) |