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Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Operating Loss Carryforwards [Line Items] |  |  |
Estimated transition tax | $ 264 |  |
Estimated tax expense for the re-measurement of deferred tax assets and liabilities | 86 |  |
Decrease in valuation allowance | 6 |  |
Undistributed earnings of foreign subsidiaries | 3,200 |  |
Benefit realized from tax holiday granted | $ 45 | $ 46 | $ 23
Earnings per share impact of tax holiday (in dollars per share) | $ 0.17 | $ 0.17 | $ 0.08
Unrecognized tax benefits that would impact effective tax rate | $ 219 | $ 240 | $ 200
Accrued potential interest and penalties | 11 | 15 | 2
Liability recorded for interest and penalties | 55 | $ 48 | $ 33
Non-US [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Estimate of local country income and withholding on undistributed earnings | $ 39 |  |

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- Definition Represents the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions. + References No definition available. + Details
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- Definition Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Provisional Income Tax Expense (Benefit) + References No definition available. + Details
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- Definition Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 11.C) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330215-122817 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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