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Securities Securities (Reconciliation of amortized cost of held to maturity securities) (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain | $ 305 | $ 90
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss | (97,170) | (143,245)
Debt Securities, Held-to-maturity, Fair Value | 1,260,752 | 1,291,801
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 1,357,617 | 1,434,956
Small Business Administration Pooled Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain | 65 | 0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss | (4,601) | (8,135)
Debt Securities, Held-to-maturity, Fair Value | 110,532 | 114,733
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 115,068 | 122,868
Collateralized Debt Obligations [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain | 0 | 0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss | (47,949) | (65,143)
Debt Securities, Held-to-maturity, Fair Value | 334,666 | 357,684
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 382,615 | 422,827
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain | 240 | 90
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss | (40,093) | (62,198)
Debt Securities, Held-to-maturity, Fair Value | 719,230 | 726,362
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | 759,083 | 788,470
US Treasury Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain | 0 | 0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss | (4,527) | (7,769)
Debt Securities, Held-to-maturity, Fair Value | 96,324 | 93,022
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | $ 100,851 | $ 100,791

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- Definition Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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