Derivatives and Hedging Activities (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	$ 301,000,000	$ 156,000,000
Cash collateral netting on interest rate contracts	(2,000,000)	(53,000,000)
Derivative asset and liability netting	(27,000,000)	(33,000,000)
Total derivatives assets,net	272,000,000	70,000,000
Other Assets [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	173,000,000	94,000,000
Other Assets [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	128,000,000	62,000,000
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	22,000,000	64,000,000
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	151,000,000	30,000,000
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	98,000,000	55,000,000
Cash collateral netting on interest rate contracts	(49,000,000)	0
Derivative asset and liability netting	(27,000,000)	(33,000,000)
Total derivatives liabilities, net	22,000,000	22,000,000
Other Liabilities [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	70,000,000	22,000,000
Other Liabilities [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liability	28,000,000	33,000,000
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	69,000,000	9,000,000
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	$ 1,000,000	$ 13,000,000

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