Derivative Financial Instruments - Amounts Related to Fair Value Hedges (Details) - Fair Value Hedges - Interest Rate Contracts - Net interest income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Net income (expense) recognized	$ 17	$ 42
AFS securities
Derivative Instruments, Gain (Loss) [Line Items]
Amounts related to interest settlements	(2)	(3)
Recognized on derivatives	11	0
Recognized on hedged items	(11)	0
Net income (expense) recognized	(2)	(3)
Loans and leases
Derivative Instruments, Gain (Loss) [Line Items]
Amounts related to interest settlements	0	(1)
Recognized on derivatives	3	0
Recognized on hedged items	(3)	0
Net income (expense) recognized	0	(1)
Long-term debt
Derivative Instruments, Gain (Loss) [Line Items]
Amounts related to interest settlements	8	46
Recognized on derivatives	(181)	0
Recognized on hedged items	192	0
Net income (expense) recognized	$ 19	$ 46

DerivativeNetHedgeIneffectivenessGainLossComponentRecognizedOnDerivative

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- Definition

DerivativeNetHedgeIneffectivenessGainLossComponentRecognizedOnHedgedItem

+ References

No definition available.

+ Details

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- Definition

GainLossOnFairValueHedgesRecognizedInNetInterestIncome

+ 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.

+ References

No definition available.

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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=84234895&loc=SL5624171-113959

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