Derivatives and Hedging Activities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	$ 49	$ 277
Derivative asset and derivative liability netting	(27)	(11)
Total derivatives assets, net	22	266
Other Assets [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	19	57
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	0
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	19	57
Other Assets [Member] \| Net Investment Hedging [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	30	220
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	160	16
Derivative asset and derivative liability netting	(27)	(11)
Total derivatives liabilities, net	133	5
Other Liabilities [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	46	10
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 liabilities	6	0
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 liabilities	40	10
Other Liabilities [Member] \| Net Investment Hedging [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	$ 114	$ 6

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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.

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No definition available.

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