Derivative Instruments and Hedging Activities - Effects of Fair Value and Cash Flow Hedge Accounting (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Interest income:
Investment Securities	$ 3,218	$ 2,873	$ 2,550
Loans, Including Loans Held for Sale	53,021	40,894	37,410
Other	2,457	2,267	1,978
Interest-bearing Deposits	(12,925)	(11,493)	(9,489)
Securitized Debt Obligations	(660)	(958)	(959)
Senior and Subordinated Notes	(2,172)	(2,333)	(2,204)
Non-interest income (expense)	1,264	1,081	1,120
Amortization expense (benefit)	69	76	79
Non-Interest Income, Other
Interest income:
Realized gain (loss) on foreign exchange contracts reclassified from AOCI	(121)	128	(66)
Fair value hedges \| Investment Securities
Interest income:
Net income (expense) recognized on fair value hedges	43	87	81
Fair value hedges \| Loans, Including Loans Held for Sale
Interest income:
Net income (expense) recognized on fair value hedges	0	0	0
Fair value hedges \| Other
Interest income:
Net income (expense) recognized on fair value hedges	0	0	0
Fair value hedges \| Interest-bearing Deposits
Interest income:
Net income (expense) recognized on fair value hedges	(102)	(324)	(388)
Fair value hedges \| Securitized Debt Obligations
Interest income:
Net income (expense) recognized on fair value hedges	(154)	(414)	(415)
Fair value hedges \| Senior and Subordinated Notes
Interest income:
Net income (expense) recognized on fair value hedges	(440)	(810)	(881)
Fair value hedges \| Non-Interest Income, Other
Interest income:
Net income (expense) recognized on fair value hedges	0	0	0
Fair value hedges \| Interest rate contracts: \| Investment Securities
Interest income:
Interest recognized on derivatives	79	159	158
Gains (losses) recognized on derivatives	(153)	(42)	(149)
Gains (losses) recognized on hedged items	117	(30)	72
Excluded component of fair value hedges	0	0	0
Fair value hedges \| Interest rate contracts: \| Loans, Including Loans Held for Sale
Interest income:
Interest recognized on derivatives	0	0	0
Gains (losses) recognized on derivatives	0	0	0
Gains (losses) recognized on hedged items	0	0	0
Excluded component of fair value hedges	0	0	0
Fair value hedges \| Interest rate contracts: \| Other
Interest income:
Interest recognized on derivatives	0	0	0
Gains (losses) recognized on derivatives	0	0	0
Gains (losses) recognized on hedged items	0	0	0
Excluded component of fair value hedges	0	0	0
Fair value hedges \| Interest rate contracts: \| Interest-bearing Deposits
Interest income:
Interest recognized on derivatives	(102)	(323)	(385)
Gains (losses) recognized on derivatives	143	116	220
Gains (losses) recognized on hedged items	(143)	(117)	(223)
Excluded component of fair value hedges	0	0	0
Fair value hedges \| Interest rate contracts: \| Securitized Debt Obligations
Interest income:
Interest recognized on derivatives	(153)	(413)	(414)
Gains (losses) recognized on derivatives	139	226	244
Gains (losses) recognized on hedged items	(140)	(227)	(245)
Excluded component of fair value hedges	0	0	0
Fair value hedges \| Interest rate contracts: \| Senior and Subordinated Notes
Interest income:
Interest recognized on derivatives	(547)	(961)	(1,036)
Gains (losses) recognized on derivatives	853	86	733
Gains (losses) recognized on hedged items	(745)	59	(575)
Excluded component of fair value hedges	(1)	6	(3)
Fair value hedges \| Interest rate contracts: \| Non-Interest Income, Other
Interest income:
Interest recognized on derivatives	0	0	0
Gains (losses) recognized on derivatives	70	(57)	42
Gains (losses) recognized on hedged items	(70)	57	(42)
Excluded component of fair value hedges	0	0	0
Cash flow hedges \| Investment Securities
Interest income:
Net income (expense) recognized on cash flow hedges	(4)	0	0
Cash flow hedges \| Loans, Including Loans Held for Sale
Interest income:
Net income (expense) recognized on cash flow hedges	(927)	(1,207)	(1,205)
Cash flow hedges \| Other
Interest income:
Net income (expense) recognized on cash flow hedges	13	11	11
Cash flow hedges \| Interest-bearing Deposits
Interest income:
Net income (expense) recognized on cash flow hedges	0	0	0
Cash flow hedges \| Securitized Debt Obligations
Interest income:
Net income (expense) recognized on cash flow hedges	0	0	0
Cash flow hedges \| Senior and Subordinated Notes
Interest income:
Net income (expense) recognized on cash flow hedges	0	0	0
Cash flow hedges \| Non-Interest Income, Other
Interest income:
Net income (expense) recognized on cash flow hedges	0	0	0
Cash flow hedges \| Interest rate contracts: \| Investment Securities
Interest income:
Realized gains (losses) reclassified from AOCI into net income	(4)	0	0
Cash flow hedges \| Interest rate contracts: \| Loans, Including Loans Held for Sale
Interest income:
Realized gains (losses) reclassified from AOCI into net income	(927)	(1,207)	(1,205)
Cash flow hedges \| Interest rate contracts: \| Other
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Interest rate contracts: \| Interest-bearing Deposits
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Interest rate contracts: \| Securitized Debt Obligations
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Interest rate contracts: \| Senior and Subordinated Notes
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Interest rate contracts: \| Non-Interest Income, Other
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Foreign exchange and other contracts \| Investment Securities
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Foreign exchange and other contracts \| Loans, Including Loans Held for Sale
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Foreign exchange and other contracts \| Other
Interest income:
Realized gains (losses) reclassified from AOCI into net income	13	11	11
Cash flow hedges \| Foreign exchange and other contracts \| Interest-bearing Deposits
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Foreign exchange and other contracts \| Securitized Debt Obligations
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Foreign exchange and other contracts \| Senior and Subordinated Notes
Interest income:
Realized gains (losses) reclassified from AOCI into net income	0	0	0
Cash flow hedges \| Foreign exchange and other contracts \| Non-Interest Income, Other
Interest income:
Realized gains (losses) reclassified from AOCI into net income	$ 0	$ 0	$ 0

Amortization of Basis Adjustment on Discontinued Hedges

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