Derivative Instruments - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Jul. 31, 2014
Derivative [Line Items]
Net derivative gains to be reclassified into earnings within the next 12 months	$ 21
Offset asset	31
Offset liability	31
Net derivative assets	59
Net derivative liabilities	$ 1
Foreign Exchange Contract \| Designated as Hedging Instrument \| Minimum
Derivative [Line Items]
Derivative contract duration	1 month
Foreign Exchange Contract \| Designated as Hedging Instrument \| Maximum
Derivative [Line Items]
Derivative contract duration	1 year
Foreign Exchange Contract \| Designated as Hedging Instrument \| Maximum \| Cash Flow Hedging
Derivative [Line Items]
Derivative contract duration	18 months
Interest Rate Swap \| Designated as Hedging Instrument \| Fair Value Hedging
Derivative [Line Items]
Derivative liability	$ 2,400	$ 2,400

Fair value of liability associated with 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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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.

+ References

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- Definition

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.

+ References

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- Definition

Fair value of asset associated with 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.

+ References

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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