Derivatives - Gains/(Losses) on Derivatives Associated with Cash Flow Hedges (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(loss) expected to be reclassified to earnings in the next twelve months	$ 25
Hedging Instruments And Hedged Items
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss), cash flow hedges	(3)	$ 13
Gain (loss) reclassified from AOCI into Interest income	1	0
Hedging Instruments And Hedged Items \| Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss), cash flow hedges	$ 8	$ 17

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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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, before 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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