Derivative Instruments and Hedging Activities (Derivative gain (loss) recognized/reclassified) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain/(loss) reclassified from AOCI into income	$ (21)	$ 46	$ 36
Gains to be reclassified within the next 12 months into interest income	205	32
Derivatives designated as hedges
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	(437)	(34)
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	(27)	62
Interest on fair value hedges	4	15
Hedge ineffectiveness / AOCI reclass due to missed forecast	(1)	0
Derivatives designated as hedges \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Terminated or redesignated, unamortized basis adjustments	10	7
Derivatives designated as hedges \| Cash Flow Hedging \| Purchased interest rate floors
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	0	0
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	2	11
Interest on fair value hedges	0	0
Hedge ineffectiveness / AOCI reclass due to missed forecast	0	0
Derivatives designated as hedges \| Cash Flow Hedging \| Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	(437)	(34)
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	(29)	51
Interest on fair value hedges	0	0
Hedge ineffectiveness / AOCI reclass due to missed forecast	0	0
Derivatives designated as hedges \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Terminated or redesignated, unamortized basis adjustments	0	1
Derivatives designated as hedges \| Fair Value Hedging \| Receive-fixed interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	0	0
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	0	0
Interest on fair value hedges	(1)	8
Hedge ineffectiveness / AOCI reclass due to missed forecast	0	0
Derivatives designated as hedges \| Fair Value Hedging \| Basis amortization on terminated hedges, liability hedges
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	0	0
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	0	0
Interest on fair value hedges	1	10
Hedge ineffectiveness / AOCI reclass due to missed forecast	0	0
Derivatives designated as hedges \| Fair Value Hedging \| Pay-fixed interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	0	0
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	0	0
Interest on fair value hedges	4	(3)
Hedge ineffectiveness / AOCI reclass due to missed forecast	(1)	0
Derivatives designated as hedges \| Fair Value Hedging \| Basis amortization on terminated hedges, asset hedges
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain/(loss) deferred in AOCI	0	0
Excluded components deferred in AOCI (amortization approach)	0	0
Amount of gain/(loss) reclassified from AOCI into income	0	0
Interest on fair value hedges	0	0
Hedge ineffectiveness / AOCI reclass due to missed forecast	$ 0	$ 0

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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-Publisher FASB
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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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The amount of net gain (loss) reclassified into earnings when interest rate cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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- Definition

Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of adjustments from accumulated other comprehensive income (AOCI) for gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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- Definition

Derivative instrument noninterest income (expense)

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Terminated And Redesignated Swaps, Unamortized Basis Adjustments

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