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
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Instruments and Other Financial Instruments Used For Hedging (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Cash flow hedges
Derivative Notional Amount	$ 155,869		$ 155,869		$ 177,428
Income from accumulated other comprehensive income expected to be reclassified to net interest income			24
Unrealized net gains (losses) on hedges arising during the period, before tax	55	$ 140	$ 36	$ 401
Cash Flow Hedges
Cash flow hedges
Weighted average remaining life of the currently active cash flow hedges			4 years
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	55	140	$ 36	401
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	20	42	49	84
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	1	0
Cash Flow Hedges \| Interest rate derivative contracts
Cash flow hedges
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	55	140		401
Cash Flow Hedges \| Interest rate derivative contracts \| Interest income
Cash flow hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	20	42
Cash Flow Hedges \| Interest rate derivative contracts \| Interest expense
Cash flow hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	0
Cash Flow Hedges \| Interest rate derivative contracts \| Noninterest expense
Cash flow hedges
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	1	$ 0
Cash Flow Hedges \| Interest rate derivative contracts \| Noninterest expense \| Maximum
Cash flow hedges
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net			3	1
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts
Cash flow hedges
Derivative Notional Amount	11,190		11,190		$ 15,459
Unrealized net gains (losses) on hedges arising during the period, before tax			36
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts \| Interest income
Cash flow hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net			49	84
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts \| Interest expense
Cash flow hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net			0	0
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts \| Noninterest expense
Cash flow hedges
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net			3	$ 1
Cash Flow Hedges \| Designated as Hedging Instrument \| Libor Indexed Loans \| Interest rate swap contracts
Cash flow hedges
Derivative Notional Amount	10,900		10,900
Cash Flow Hedges \| Designated as Hedging Instrument \| Libor Indexed Short Term Borrowings \| Interest rate swap contracts
Cash flow hedges
Derivative Notional Amount	$ 290		$ 290