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Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands | Sep. 30, 2024 USD ($) holding | Dec. 31, 2023 USD ($) 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 | 145 | 163
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 47,479 | $ 1,620
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (188) | (18)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,194,020 | 1,328,959
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (87,402) | (125,618)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,241,499 | 1,330,579
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 87,590 | $ 125,636
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 | 104 | 115
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 47,479 | $ 1,091
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (188) | (11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 266,901 | 273,447
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (29,094) | (37,235)
Debt Securities, Available-for-sale, Unrealized Loss Position | 314,380 | 274,538
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 29,282 | $ 37,246
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 | 9 | 12
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 339
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | (2)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 28,452 | 31,682
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (1,646) | (2,528)
Debt Securities, Available-for-sale, Unrealized Loss Position | 28,452 | 32,021
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 1,646 | $ 2,530
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 |  | $ 190
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | (5)
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 |  | 190
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss |  | $ 5
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 | 1,027 | 1,018
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (153) | (170)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,027 | 1,018
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 153 | $ 170
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 | 43,643 | 46,572
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (5,944) | (7,130)
Debt Securities, Available-for-sale, Unrealized Loss Position | 43,643 | 46,572
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 5,944 | $ 7,130
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 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 213,084 | 207,138
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (16,558) | (23,060)
Debt Securities, Available-for-sale, Unrealized Loss Position | 213,084 | 207,138
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 16,558 | $ 23,060
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 | 14 | 17
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 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 640,913 | 769,102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (34,007) | (55,495)
Debt Securities, Available-for-sale, Unrealized Loss Position | 640,913 | 769,102
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 34,007 | $ 55,495

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