Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Description of the relevant terms of the derivative. Includes the type of instrument, risk being hedged, notional amount, counterparty, inception date, maturity date, relevant interest rates, strike price, cap price, and floor price.

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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before tax 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).

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Derivative Financial Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Derivative [Line Items]
Loss on derivatives to be reclassified within the next twelve months			$ (10)
Maximum [Member]
Derivative [Line Items]
Longest outstanding maturity			2 years 2 months 12 days
Not Designated as Hedging Instrument [Member] \| Forward exchange contracts [Member]
Derivative [Line Items]
Derivative, notional amount	$ 382		$ 382		$ 971
Derivative liability, fair value	1		1
Derivative asset, fair value					3
Not Designated as Hedging Instrument [Member] \| Forward exchange contracts [Member] \| Other income, net [Member]
Derivative [Line Items]
(Loss)/gain recognized in income	(1)	$ (3)	$ (4)	$ 6
Cash Flow Hedges [Member] \| Designated as Hedging Instrument [Member] \| Interest rate swaps [Member]
Derivative [Line Items]
Derivative, notional amount					300
Derivative liability, fair value					1
Derivative maturity description			third quarter of 2018
Cash Flow Hedges [Member] \| Designated as Hedging Instrument [Member] \| Forward exchange contracts [Member]
Derivative [Line Items]
Derivative, notional amount	537		$ 537		937
Derivative liability, fair value	11		11		$ 21
(Loss)/gain recognized in OCI (effective portion)	(5)	12	(14)	24
Loss reclassified from Accumulated OCL into income (effective element)	(6)	(10)	(24)	(53)
Gain recognized in income (ineffective portion and amount excluded from effectiveness testing)	$ 0	$ 0	$ 0	$ 1