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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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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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.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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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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Derivative Instruments and Other Financial Instruments Used For Hedging - Amount and Location of Gains and Losses for Derivatives Designated as Cash Flow Hedges (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Cash flow hedges
Notional Amount	$ 177,086,000,000		$ 177,086,000,000		$ 177,428,000,000
Income from accumulated other comprehensive income expected to be reclassified to net interest income			$ 11,000,000
Cash Flow Hedges
Cash flow hedges
Weighted average remaining life of the currently active cash flow hedges			3 years 7 months 6 days
Interest rate contracts, Amount of Gain or (Loss) Recognized in OCI on Derivative Instruments (Effective Portion)	6,000,000	$ (60,000,000)	$ 42,000,000	$ 341,000,000
Interest rate contracts, Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	11,000,000	43,000,000	60,000,000	127,000,000
Cash Flow Hedges \| Noninterest expense
Cash flow hedges
Interest rate contracts, (Gain) Loss Recognized in Income on Derivative Instruments (Ineffective Portion)	0	0	3,000,000	1,000,000
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts
Cash flow hedges
Notional Amount	10,600,000,000		10,600,000,000		$ 15,459,000,000
Interest rate contracts, Amount of Gain or (Loss) Recognized in OCI on Derivative Instruments (Effective Portion)	6,000,000	(60,000,000)	42,000,000	341,000,000
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts \| Interest income
Cash flow hedges
Interest rate contracts, Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	11,000,000	43,000,000	60,000,000	127,000,000
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts \| Interest expense
Cash flow hedges
Interest rate contracts, Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	0	0	0	0
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts \| Noninterest expense
Cash flow hedges
Interest rate contracts, (Gain) Loss Recognized in Income on Derivative Instruments (Ineffective Portion)	0	$ 0	3,000,000	$ 1,000,000
Cash Flow Hedges \| Designated as Hedging Instrument \| Libor Indexed Loans \| Interest rate swap contracts
Cash flow hedges
Notional Amount	10,400,000,000		10,400,000,000
Cash Flow Hedges \| Designated as Hedging Instrument \| Libor Indexed Short Term Borrowings \| Interest rate swap contracts
Cash flow hedges
Notional Amount	$ 200,000,000		$ 200,000,000