Investment Securities - Amortized Costs and Estimated Fair Values (Details) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
|
| Available-for-sale securities | |||||
| Amortized cost | $ 560,207,000,000 | $ 560,207,000,000 | $ 507,226,000,000 | ||
| Unallocated portfolio layer fair value basis adjustments, Amortized cost | (3,176,000,000) | (3,176,000,000) | 641,000,000 | ||
| Gross unrealized gains | 654,000,000 | 654,000,000 | 3,314,000,000 | ||
| Unallocated portfolio layer fair value basis adjustments, Gross unrealized gains | 0 | 0 | (641,000,000) | ||
| Gross unrealized losses | 13,670,000,000 | 13,670,000,000 | 3,342,000,000 | ||
| Unallocated portfolio layer fair value basis adjustments, Gross unrealized losses | (3,176,000,000) | (3,176,000,000) | 0 | ||
| Fair value | 547,191,000,000 | 547,191,000,000 | 507,198,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 274,564,000,000 | 274,564,000,000 | 270,134,000,000 | ||
| Gross unrealized gains | 10,000,000 | 10,000,000 | 263,000,000 | ||
| Gross unrealized losses | 25,841,000,000 | 25,841,000,000 | 17,053,000,000 | ||
| Fair value | 248,733,000,000 | 248,733,000,000 | 253,344,000,000 | ||
| Total investment securities, net of allowance for credit losses | |||||
| Amortized cost | 834,771,000,000 | 834,771,000,000 | 777,360,000,000 | ||
| Gross unrealized gains | 664,000,000 | 664,000,000 | 3,577,000,000 | ||
| Gross unrealized losses | 39,511,000,000 | 39,511,000,000 | 20,395,000,000 | ||
| Fair value | 795,924,000,000 | 795,924,000,000 | 760,542,000,000 | ||
| HTM securities purchased | 14,100,000,000 | $ 1,600,000,000 | 37,200,000,000 | $ 4,800,000,000 | |
| Investment securities, allowance for credit losses | 47,000,000 | 105,000,000 | 47,000,000 | 105,000,000 | 106,000,000 |
| Accrued interest receivables on investment securities | 5,500,000,000 | 5,500,000,000 | 4,600,000,000 | ||
| Accrued interest receivables reversed through interest income on AFS securities | 0 | 0 | 0 | 0 | |
| Accrued interest receivables reversed through interest income on HTM securities | 0 | $ 0 | 0 | $ 0 | |
| Total mortgage-backed securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 109,044,000,000 | 109,044,000,000 | 102,547,000,000 | ||
| Gross unrealized gains | 103,000,000 | 103,000,000 | 1,162,000,000 | ||
| Gross unrealized losses | 5,505,000,000 | 5,505,000,000 | 2,262,000,000 | ||
| Fair value | 103,642,000,000 | 103,642,000,000 | 101,447,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 94,311,000,000 | 94,311,000,000 | 103,108,000,000 | ||
| Gross unrealized gains | 0 | 0 | 82,000,000 | ||
| Gross unrealized losses | 14,780,000,000 | 14,780,000,000 | 10,004,000,000 | ||
| Fair value | 79,531,000,000 | 79,531,000,000 | 93,186,000,000 | ||
| U.S. GSEs and government agencies mortgage-backed securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 97,749,000,000 | 97,749,000,000 | 92,112,000,000 | ||
| Gross unrealized gains | 95,000,000 | 95,000,000 | 1,075,000,000 | ||
| Gross unrealized losses | 5,326,000,000 | 5,326,000,000 | 2,215,000,000 | ||
| Fair value | 92,518,000,000 | 92,518,000,000 | 90,972,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 82,191,000,000 | 82,191,000,000 | 89,073,000,000 | ||
| Gross unrealized gains | 0 | 0 | 57,000,000 | ||
| Gross unrealized losses | 13,545,000,000 | 13,545,000,000 | 9,200,000,000 | ||
| Fair value | 68,646,000,000 | 68,646,000,000 | 79,930,000,000 | ||
| Residential: U.S. Mortgage-backed securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 5,768,000,000 | 5,768,000,000 | 5,564,000,000 | ||
| Gross unrealized gains | 1,000,000 | 1,000,000 | 38,000,000 | ||
| Gross unrealized losses | 105,000,000 | 105,000,000 | 17,000,000 | ||
| Fair value | 5,664,000,000 | 5,664,000,000 | 5,585,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 6,734,000,000 | 6,734,000,000 | 7,542,000,000 | ||
| Gross unrealized gains | 0 | 0 | 6,000,000 | ||
| Gross unrealized losses | 860,000,000 | 860,000,000 | 570,000,000 | ||
| Fair value | 5,874,000,000 | 5,874,000,000 | 6,978,000,000 | ||
| Residential: Non-U.S. mortgage-backed securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 184,000,000 | 184,000,000 | 405,000,000 | ||
| Gross unrealized gains | 1,000,000 | 1,000,000 | 1,000,000 | ||
| Gross unrealized losses | 0 | 0 | 0 | ||
| Fair value | 185,000,000 | 185,000,000 | 406,000,000 | ||
| Commercial mortgage-backed securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 5,343,000,000 | 5,343,000,000 | 4,466,000,000 | ||
| Gross unrealized gains | 6,000,000 | 6,000,000 | 48,000,000 | ||
| Gross unrealized losses | 74,000,000 | 74,000,000 | 30,000,000 | ||
| Fair value | 5,275,000,000 | 5,275,000,000 | 4,484,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 5,386,000,000 | 5,386,000,000 | 6,493,000,000 | ||
| Gross unrealized gains | 0 | 0 | 19,000,000 | ||
| Gross unrealized losses | 375,000,000 | 375,000,000 | 234,000,000 | ||
| Fair value | 5,011,000,000 | 5,011,000,000 | 6,278,000,000 | ||
| U.S. Treasury and government agencies | |||||
| Available-for-sale securities | |||||
| Amortized cost | 355,248,000,000 | 355,248,000,000 | 313,470,000,000 | ||
| Gross unrealized gains | 458,000,000 | 458,000,000 | 2,384,000,000 | ||
| Gross unrealized losses | 7,981,000,000 | 7,981,000,000 | 32,000,000 | ||
| Fair value | 347,725,000,000 | 347,725,000,000 | 315,822,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 154,825,000,000 | 154,825,000,000 | 132,727,000,000 | ||
| Gross unrealized gains | 0 | 0 | 134,000,000 | ||
| Gross unrealized losses | 9,912,000,000 | 9,912,000,000 | 6,414,000,000 | ||
| Fair value | 144,913,000,000 | 144,913,000,000 | 126,447,000,000 | ||
| Obligations of U.S. states and municipalities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 18,336,000,000 | 18,336,000,000 | 20,915,000,000 | ||
| Gross unrealized gains | 18,000,000 | 18,000,000 | 118,000,000 | ||
| Gross unrealized losses | 2,301,000,000 | 2,301,000,000 | 793,000,000 | ||
| Fair value | 16,053,000,000 | 16,053,000,000 | 20,240,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 7,939,000,000 | 7,939,000,000 | 8,600,000,000 | ||
| Gross unrealized gains | 0 | 0 | 17,000,000 | ||
| Gross unrealized losses | 1,125,000,000 | 1,125,000,000 | 609,000,000 | ||
| Fair value | 6,814,000,000 | 6,814,000,000 | 8,008,000,000 | ||
| Non-U.S. government debt securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 50,839,000,000 | 50,839,000,000 | 45,676,000,000 | ||
| Gross unrealized gains | 35,000,000 | 35,000,000 | 215,000,000 | ||
| Gross unrealized losses | 1,028,000,000 | 1,028,000,000 | 236,000,000 | ||
| Fair value | 49,846,000,000 | 49,846,000,000 | 45,655,000,000 | ||
| Corporate debt securities | |||||
| Available-for-sale securities | |||||
| Amortized cost | 215,000,000 | 215,000,000 | 139,000,000 | ||
| Gross unrealized gains | 0 | 0 | 0 | ||
| Gross unrealized losses | 7,000,000 | 7,000,000 | 11,000,000 | ||
| Fair value | 208,000,000 | 208,000,000 | 128,000,000 | ||
| Asset-backed securities: Collateralized loan obligations | |||||
| Available-for-sale securities | |||||
| Amortized cost | 27,898,000,000 | 27,898,000,000 | 21,897,000,000 | ||
| Gross unrealized gains | 30,000,000 | 30,000,000 | 51,000,000 | ||
| Gross unrealized losses | 0 | 0 | 1,000,000 | ||
| Fair value | 27,928,000,000 | 27,928,000,000 | 21,947,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 16,736,000,000 | 16,736,000,000 | 24,695,000,000 | ||
| Gross unrealized gains | 10,000,000 | 10,000,000 | 29,000,000 | ||
| Gross unrealized losses | 2,000,000 | 2,000,000 | 6,000,000 | ||
| Fair value | 16,744,000,000 | 16,744,000,000 | 24,718,000,000 | ||
| Asset-backed securities: Other | |||||
| Available-for-sale securities | |||||
| Amortized cost | 1,803,000,000 | 1,803,000,000 | 1,941,000,000 | ||
| Gross unrealized gains | 10,000,000 | 10,000,000 | 25,000,000 | ||
| Gross unrealized losses | 24,000,000 | 24,000,000 | 7,000,000 | ||
| Fair value | 1,789,000,000 | 1,789,000,000 | 1,959,000,000 | ||
| Held-to-maturity securities | |||||
| Amortized cost | 753,000,000 | 753,000,000 | 1,004,000,000 | ||
| Gross unrealized gains | 0 | 0 | 1,000,000 | ||
| Gross unrealized losses | 22,000,000 | 22,000,000 | 20,000,000 | ||
| Fair value | $ 731,000,000 | $ 731,000,000 | $ 985,000,000 | ||