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v3.25.2

Investment securities - Additional Information (Detail) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 USD ($) security | Jun. 30, 2024 USD ($) | Jun. 30, 2025 USD ($) security | Jun. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |  |  |  |
Realized gain | $ 0 | $ 0 | $ 0 | $ 0 |
Number of debt securities with aggregate gross unrealized losses | security | 3,427 |  | 3,427 |  |
Unrealized losses on individual debt securities |  |  | $ 1,100,000,000 |  |
Cost method equity securities | $ 730,000,000 |  | 730,000,000 |  |
Allowance for credit losses | 0 |  | 0 |  | $ 0
Investment securities pledged to secure debt carrying value | 5,800,000,000 |  | 5,800,000,000 |  | 6,200,000,000
Carrying value of investment securities pledged related to repurchase transactions | $ 82,000,000 |  | $ 82,000,000 |  | $ 71,000,000

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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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