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Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands | Sep. 30, 2025 USD ($) holding | Dec. 31, 2024 USD ($) holding
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Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 214 | 160
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 293,114 | $ 128,499
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (3,664) | (2,874)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,033,817 | 1,119,582
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (60,940) | (100,172)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,326,931 | 1,248,081
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 64,604 | $ 103,046
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 111 | 117
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 96,770 | $ 127,152
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (481) | (2,867)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 292,217 | 249,098
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (24,222) | (34,915)
Debt Securities, Available-for-sale, Unrealized Loss Position | 388,987 | 376,250
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 24,703 | $ 37,782
Collateralized Debt Obligations [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 57 | 11
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 180,392 | $ 1,153
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (3,116) | (4)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 24,341 | 26,890
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (1,514) | (2,170)
Debt Securities, Available-for-sale, Unrealized Loss Position | 204,733 | 28,043
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 4,630 | $ 2,174
US States and Political Subdivisions Debt Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding |  | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months |  | $ 194
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | (3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer |  | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0
Debt Securities, Available-for-sale, Unrealized Loss Position |  | 194
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss |  | $ 3
Pooled trust preferred securities issued by banks and insurers |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 1 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,040 | 1,095
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (80) | (85)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,040 | 1,095
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 80 | $ 85
Small Business Administration Pooled Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 8 | 8
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 38,577 | 40,838
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (5,179) | (7,194)
Debt Securities, Available-for-sale, Unrealized Loss Position | 38,577 | 40,838
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 5,179 | $ 7,194
U.S. government agency securities |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 9 | 9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 217,175 | 209,660
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (11,714) | (19,792)
Debt Securities, Available-for-sale, Unrealized Loss Position | 217,175 | 209,660
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 11,714 | $ 19,792
US Treasury Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 10 | 13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 460,467 | 592,001
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (18,231) | (36,016)
Debt Securities, Available-for-sale, Unrealized Loss Position | 460,467 | 592,001
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 18,231 | $ 36,016
Taxable Municipal Bonds |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding | 18 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 15,952 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (67) |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 |
Debt Securities, Available-for-sale, Unrealized Loss Position | 15,952 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 67 |

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