Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Estimated loss to be reclassified from AOCI	$ 74
Designated as Hedging Instrument \| Interest rate swaps \| Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amounts	66,500	$ 18,700
Designated as Hedging Instrument \| Interest rate swaps \| Fair Value Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amounts	68,200	$ 42,200
Margin Loans \| Designated as Hedging Instrument \| Interest rate swaps \| Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amounts	43,600
Underlying principal	20,000
PALs \| Designated as Hedging Instrument \| Interest rate swaps \| Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amounts	22,900
Underlying principal	19,800
Senior Notes \| Designated as Hedging Instrument \| Interest rate swaps \| Fair Value Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amounts	57,000
Underlying principal	19,500
AFS securities \| Designated as Hedging Instrument \| Interest rate swaps \| Fair Value Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amounts	11,200
Underlying principal	$ 11,200