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Securities (Reconciliation of fair value of available for sale securities) (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | $ 1,998,347 | $ 1,353,964
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 7,477 | 26
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (64,604) | (103,046)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,941,220 | 1,250,944
U.S. government agency securities |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 228,889 | 229,452
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 0 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (11,714) | (19,792)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 217,175 | 209,660
U.S. treasury securities |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 485,194 | 628,017
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 14 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (18,231) | (36,016)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 466,977 | 592,001
Agency mortgage-backed securities |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 727,744 | 415,918
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 4,224 | 25
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (24,703) | (37,782)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 707,265 | 378,161
Agency Collateralized Mortgage Obligations [Member] |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 279,977 | 31,168
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 830 | 1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (4,630) | (2,174)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 276,177 | 28,995
US States and Political Subdivisions Debt Securities [Member] |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 14,611 | 197
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 54 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 0 | (3)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 14,665 | 194
Taxable Municipal Bonds |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 217,056 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 2,355 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (67) | 0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 219,344 | 0
Pooled trust preferred securities issued by banks and insurers |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 1,120 | 1,180
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 0 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (80) | (85)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 1,040 | 1,095
Small Business Administration Pooled Securities [Member] |  |
Reconciliation of fair value of securities |  |
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss | 43,756 | 48,032
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 0 | 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (5,179) | (7,194)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest | $ 38,577 | $ 40,838

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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