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Investment Securities - Schedule of Realized Gain (Loss) (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract] |  |  |
Proceeds from sales | $ 2,142,462 | $ 789,603 | $ 172,947
Gross realized gains | 2,240 | 0 | 0
Gross realized losses | (141,034) | (37,356) | $ (6,751)
Gross losses realized on sale of available-for-sale securities | 2,600 | 3,800 |
Included in non-interest income | $ 136,200 | $ 33,600 |

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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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