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Other Financial Data - Schedule of Other Income (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Other Financial Data [Abstract] |  |  |
Foreign currency remeasurement gain (loss) | $ (37) | $ (2) | $ 30
Net gain (loss) on disposal of businesses | (16) | 39 | 82
Equity earnings | 12 | 13 | 13
Income (loss) on financial instruments | 2 | (14) | (24)
Other | 0 | 0 | (1)
Other income | $ (39) | $ 36 | $ 100

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