Derivatives and Hedging Activities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Total fair value of derivatives assets	$ 235	$ 765
Total fair value of derivatives liabilties	327	280
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Cash collateral netting	17	54
Derivative asset and liability netting	(92)	(157)
Total derivative assets	126	555
Other Assets [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives assets	67	458
Other Assets [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives assets	26	111
Other Assets [Member] \| Foreign exchange contracts [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives assets	41	347
Other Assets [Member] \| Foreign exchange contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives assets	168	308
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Cash collateral netting	(8)	(68)
Derivative asset and liability netting	(92)	(157)
Total derivative liabilities	227	55
Other Liabilities [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives liabilties	225	104
Other Liabilities [Member] \| Foreign exchange contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives liabilties	102	176
Other Liabilities [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives liabilties	15	69
Other Liabilities [Member] \| Net Investment Hedging [Member] \| Foreign exchange contracts [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivatives liabilties	210	35
Individually Significant Counterparties [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets	0	0
Total derivative liabilities	$ 0	$ 0

Represents the netting of cash collateral received and posted under credit support agreements.

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- Definition

Represents the netting of derivative assets and liabilities under master netting agreements.

+ References

No definition available.

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- Definition

Fair value, before 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 elected not to be offset. Includes assets not subject to a master netting arrangement.

+ References

No definition available.

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Fair value, before effects of master netting arrangements, of a financial liability 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 elected not to be offset. Includes assets not subject to a master netting arrangement.

+ References

No definition available.

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- Definition

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

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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