Derivatives and Hedging Activities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	$ 68	$ 301
Total fair value of derivative liability	121	98
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	68	301
Cash collateral netting	0	(2)
Derivative asset and derivative liability netting	(38)	(27)
Total derivatives assets	30	272
Other Assets [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	18	173
Other Assets [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	50	128
Other Assets [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	0	22
Other Assets [Member] \| Net Investment Hedging [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	18	151
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	121	98
Cash collateral netting	0	(49)
Derivative asset and derivative liability netting	(38)	(27)
Total derivatives liabilities	83	22
Other Liabilities [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	71	70
Other Liabilities [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	50	28
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 derivative liability	8	69
Other Liabilities [Member] \| Net Investment Hedging [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	$ 63	$ 1

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- Definition

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+ 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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+ References

No definition available.

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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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+ 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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