| **Consolidated Statements of Changes in Shareholder's Equity - USD ($) $ in Millions** | Total   | Common stock | Additional paid-in capital | Retained earnings | Accumulated other comprehensive income/(loss) | Noncontrolling interests |
|----------------------------------------------------------------------------------------|---------|--------------|----------------------------|-------------------|-----------------------------------------------|--------------------------|
| Balance at Dec. 31, 2016                                                               | $ 2,985 | $ 745        | $ 2                        | $ 3,108           | $ (995)                                       | $ 125                    |
| **Increase (Decrease) in Shareholder's Equity [Roll Forward]**                         |    |         |                       |              |                                          |                     |
| Profit of consolidated companies                                                       | 320     |         |                       | 315               |                                          | 5                        |
| Foreign currency translation, net of tax                                               | 395     |         |                       |              | 389                                           | 6                        |
| Derivative financial instruments, net of tax                                           | 0       |         |                       |              | 0                                             |                     |
| Balance at Sep. 30, 2017                                                               | 3,700   | 745          | 2                          | 3,423             | (606)                                         | 136                      |
| Balance at Dec. 31, 2017                                                               | 3,264   | 745          | 2                          | 2,969             | (592)                                         | 140                      |
| **Increase (Decrease) in Shareholder's Equity [Roll Forward]**                         |    |         |                       |              |                                          |                     |
| Profit of consolidated companies                                                       | 302     |         |                       | 287               |                                          | 15                       |
| Foreign currency translation, net of tax                                               | (241)   |         |                       |              | (233)                                         | (8)                      |
| Derivative financial instruments, net of tax                                           | (3)     |         |                       |              | (3)                                           |                     |
| Balance at Sep. 30, 2018                                                               | $ 3,322 | $ 745        | $ 2                        | $ 3,256           | $ (828)                                       | $ 147                    |

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| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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| - Definition
Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).
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| - Definition
Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.
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| - Definition
Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.
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