Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, income tax benefit	$ 2	$ 1	$ 3	$ 0
Foreign currency reclassification to earnings, net of income tax (expense) benefit	0	0	0	0
Change in derivative fair value, net of income tax (expense) benefit	(3)	(6)	(3)	15
Derivative reclassification to earnings, net of income tax (expense) benefit	(7)	5	(15)	(6)
Pension, Reclassifications to Earnings, Net of Income Tax (expense) benefit	$ 0	$ (4)	$ (2)	$ (10)

Amount of tax expense (benefit), before 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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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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Amount of tax expense (benefit), before reclassification adjustments, related to 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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