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, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Net income (expense) recognized	$ 13	$ (16)
AFS securities
Derivative Instruments, Gain (Loss) [Line Items]
Amounts related to interest settlements	0	0
Recognized on derivatives	0	(7)
Recognized on hedged items	(2)	5
Net income (expense) recognized	(2)	(2)
Loans and leases
Derivative Instruments, Gain (Loss) [Line Items]
Amounts related to interest settlements	0	0
Recognized on derivatives	(3)	(8)
Recognized on hedged items	2	8
Net income (expense) recognized	(1)	0
Long-term debt
Derivative Instruments, Gain (Loss) [Line Items]
Amounts related to interest settlements	16	(22)
Recognized on derivatives	922	116
Recognized on hedged items	(922)	(108)
Net income (expense) recognized	$ 16	$ (14)

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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

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Amount of gain (loss) on derivative instrument designated and qualifying as fair value hedge included in assessment of hedge effectiveness, recognized in earnings.

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

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