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Basis of Presentation (Reclassification) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Jun. 30, 2016 | Sep. 30, 2016 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | $ 459 | $ 326 | $ 308 | $ 337 | $ 540 | $ 311 | $ 214 | $ 357 | $ 645 | $ 971 | $ 1,430 | $ 1,422 | $ 1,431
Investments | 119 |  |  |  | 135 |  |  |  |  |  | 119 | 135 |
Purchases of shares from noncontrolling interests |  |  |  |  |  |  |  |  |  |  | (77) | (39) | 4
Receivables, net |  |  |  | 97 |  |  |  |  | 128 | 228 | (86) | (83) | (25)
Other assets and liabilities |  |  |  | 72 |  |  |  |  | 65 | 94 | 50 | 118 | (43)
Increase (decrease) in restructuring reserve |  |  |  |  |  |  |  |  |  |  |  | 31 | 83
Accounts Receivable |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Reclassification adjustment |  |  |  |  |  |  |  |  |  |  | 170 | 170 | 170
Non-current Deferred Tax Asset |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Reclassification adjustment |  |  |  |  |  |  |  |  |  |  | (66) | (66) | (66)
Retained Earnings |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Reclassification adjustment |  |  |  |  |  |  |  |  |  |  | (104) | (104) | $ (104)
Scenario, Previously Reported |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | 509 | 314 | 280 | 327 | 590 | 303 | 188 | 341 | 607 | 921 | 1,430 | 1,422 |
Receivables, net |  |  |  | 110 |  |  |  |  | 175 | 289 |  |  |
Other assets and liabilities |  |  |  | 69 |  |  |  |  | 56 | 83 |  |  |
Restatement Adjustment |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | $ (50) | $ 12 | $ 28 | 10 | $ (50) | $ 8 | $ 26 | $ 16 |  |  | $ 0 | $ 0 |
Adjustments for New Accounting Pronouncement | Restatement Adjustment |  |  |  |  |  |  |  |  |  |  |  |  |
Summary of Reclassification From Prior Period [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net income |  |  |  | 10 |  |  |  |  | 38 | 50 |  |  |
Receivables, net |  |  |  | (13) |  |  |  |  | (47) | (61) |  |  |
Other assets and liabilities |  |  |  | $ 3 |  |  |  |  | $ 9 | $ 11 |  |  |

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