Investment in securities - Investment Maturities (Details) - USD ($) $ in Thousands |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Available-for-sale | ||
| Within 1 year | $ 548,825 | |
| 1 to 5 years | 793,259 | |
| 5 to 10 years | 0 | |
| Over 10 years | 0 | |
| No specific or single maturity | 1,354,169 | |
| Carrying amount | 2,696,253 | $ 2,272,486 |
| US government and federal agencies | ||
| Available-for-sale | ||
| Within 1 year | 548,825 | |
| 1 to 5 years | 793,259 | |
| 5 to 10 years | 0 | |
| Over 10 years | 0 | |
| No specific or single maturity | 1,340,387 | |
| Carrying amount | 2,682,471 | 2,163,619 |
| Held-to-maturity | ||
| Within 1 year | 0 | |
| 1 to 5 years | 0 | |
| 5 to 10 years | 0 | |
| Over 10 years | 0 | |
| No specific or single maturity | 2,992,052 | |
| Carrying amount | 2,992,052 | |
| Residential mortgage-backed securities | ||
| Available-for-sale | ||
| Within 1 year | 0 | |
| 1 to 5 years | 0 | |
| 5 to 10 years | 0 | |
| Over 10 years | 0 | |
| No specific or single maturity | 13,782 | |
| Carrying amount | $ 13,782 | $ 15,359 |
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- Definition Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Within 1 year No definition available.
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- Definition Debt Securities, Held-to-Maturity, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Within 1 year No definition available.
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- References No definition available.
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) without single maturity date and not allocated over maturity grouping. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Details
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