Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Average remaining period until maturity of the derivative contract, 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

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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- Definition

Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

+ References

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- Definition

Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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Derivative Instruments and Other Financial Instruments Used For Hedging (Details 2) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2017	Dec. 31, 2015
Cash flow hedges
Derivative Notional Amount	$ 128,725			$ 129,600
Cash Flow Hedges
Cash flow hedges
Weighted average remaining life of the currently active cash flow hedges	3 years 5 months 1 day
Interest rate derivative contracts \| Fair value hedges
Cash flow hedges
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ 7	$ 5
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	(7)	(4)
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	0	1
Designated as Hedging Instrument \| Interest rate derivative contracts \| Fair value hedges
Cash flow hedges
Gain (Loss) on Fair Value Hedges Recognized in Earnings	7	5
Derivative Notional Amount	500			500
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	(7)	(4)
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	0	$ 1
Designated as Hedging Instrument \| Interest rate derivative contracts \| Cash Flow Hedges
Cash flow hedges
Derivative Notional Amount	14,300			$ 15,250
Libor Indexed Loans [Member] \| Designated as Hedging Instrument \| Interest Rate Swap [Member] \| Cash Flow Hedges
Cash flow hedges
Derivative Notional Amount	$ 14,300
Scenario, Forecast [Member]
Cash flow hedges
Income from accumulated other comprehensive income expected to be reclassified to net interest income			$ 140