Derivatives and Hedging Activities - Narrative (Details) $ in Millions	6 Months Ended
	Jun. 30, 2024 USD ($) group	Dec. 31, 2023 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative assets after effects of bilateral collateral and master netting agreements	$ 5
Derivative liabilities after effects of bilateral collateral and master netting agreements	5
Derivative assets not designated as hedging instruments after effects of bilateral collateral and master netting agreements, and a reserve for potential future losses	225
Derivative liabilities not designated as hedging instruments after effects of bilateral collateral and master netting agreements, and a reserve for potential future losses	1,200
Reclassify of after-tax net losses on derivative instruments from AOCI	429
Reclassification of net losses related to terminated cash flow hedges from AOCI to income	$ 62
Maximum length of time over which forecasted transactions are hedged (in years)	3 years 10 months 9 days
Cash collateral netted against derivative assets	$ 223	$ 408
Collateral netted against derivative liabilities	$ 158	64
Number of derivative transactions group | group	2
Gross exposure on derivatives, after taking into account the effects of bilateral collateral and master netting agreements	$ 366
Net exposure on derivatives, after taking into account, the effects of bilateral collateral and master netting agreements	35
Over-collateralization on derivatives to broker-dealers and banks, after the application of master netting agreements and collateral	28
Additional collateral aggregate fair value	7
Default reserve associated with uncollateralized contracts	5
Gross exposure on derivatives after taking into account effects of master netting agreements	222
Net exposure on derivatives with clients after application of master netting agreements collateral and related reserve	189
Net liability position	$ 1	$ 1