| **CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions** | 12 Months Ended |
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| **Statement of Comprehensive Income [Abstract]**                                   |            |   |   |
| Net income                                                                         | $ 553           | $ 324 | $ 334 |
| **Other comprehensive income (loss):**                                             |            |   |   |
| Foreign currency translation loss, net of income taxes                             | (34)            | (69) | (69) |
| Net unrealized gain (loss) on hedging derivatives, net of income taxes             | 1               | 1 | (19) |
| Amortization of gain on treasury lock, net of income taxes                         | 0               | 0 | 2 |
| Net unrecognized gain (loss) on postretirement obligations, net of income taxes    | 200             | (411) | 85 |
| Other comprehensive income (loss), net of income taxes                             | 167             | (479) | (1) |
| Total comprehensive income (loss)                                                  | $ 720           | $ (155) | $ 333 |

| X                                                                                                                                                                                                                                                                                                                             |
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| - Definition
Other Comprehensive Income Loss On Treasury Lock During Period Net Of Tax.
+ References
No definition available.
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| - Definition
Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.
+ References
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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).
+ References
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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
Amount after tax and reclassification adjustments of other comprehensive income (loss).
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| - Definition
Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.
+ References
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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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