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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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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-Publisher FASB
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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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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 - Amount and Location of Gains and Losses for Derivatives Designated as Cash Flow Hedges (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Cash flow hedges
Notional Amount	$ 119,015		$ 119,015		$ 150,854
Income from accumulated other comprehensive income expected to be reclassified to net interest income			69
Unrealized net gains (losses) on hedges arising during the period, before tax	(19)	$ 55
Cash Flow Hedges
Cash flow hedges
Interest rate contracts, Amount of Gain or (Loss) Recognized in OCI on Derivative Instruments (Effective Portion)	(19)	55	(98)	$ 36
Interest rate contracts, Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(8)	20	(8)	49
Cash Flow Hedges \| Noninterest expense
Cash flow hedges
Interest rate contracts, (Gain) Loss Recognized in Income on Derivative Instruments (Ineffective Portion)	(1)	1	(1)	3
Cash Flow Hedges \| Designated as Hedging Instrument \| Interest rate derivative contracts
Cash flow hedges
Notional Amount	181		181		$ 6,998
Interest rate contracts, Amount of Gain or (Loss) Recognized in OCI on Derivative Instruments (Effective Portion)	(19)	55		36
Unrealized net gains (losses) on hedges arising during the period, before tax			(98)
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)	(8)	20	(8)	49
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)	(1)	$ 1	(1)	$ 3
Cash Flow Hedges \| Designated as Hedging Instrument \| Libor Indexed Short Term Borrowings \| Interest rate swap contracts
Cash flow hedges
Notional Amount	$ 181		$ 181