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Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands | Mar. 31, 2023 USD ($) holding | Dec. 31, 2022 USD ($) 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 | 168 | 173
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 62,247 | $ 333,099
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (2,856) | (35,411)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,340,161 | 1,062,964
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (142,648) | (132,268)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,402,408 | 1,396,063
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 145,504 | $ 167,679
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 | 119 | 123
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 43,406 | $ 155,944
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (2,007) | (15,186)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 259,616 | 154,653
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (38,618) | (30,248)
Debt Securities, Available-for-sale, Unrealized Loss Position | 303,022 | 310,597
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 40,625 | $ 45,434
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 | 13 | 13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 3,039 | $ 38,843
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (32) | (3,031)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 34,851 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (2,562) | 0
Debt Securities, Available-for-sale, Unrealized Loss Position | 37,890 | 38,843
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 2,594 | $ 3,031
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 |  | $ 191
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 |  | 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 |  | 191
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss |  | $ 2
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 | 1,042 | 1,034
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (161) | (169)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,042 | 1,034
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 161 | $ 169
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 | $ 3,933 | $ 34,511
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (201) | (3,550)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 46,820 | 17,246
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (6,694) | (4,163)
Debt Securities, Available-for-sale, Unrealized Loss Position | 50,753 | 51,757
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 6,895 | $ 7,713
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 | $ 11,869 | $ 60,575
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (616) | (7,292)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 193,145 | 141,725
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (25,123) | (21,344)
Debt Securities, Available-for-sale, Unrealized Loss Position | 205,014 | 202,300
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 25,739 | $ 28,636
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 | 18 | 18
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 43,035
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | (6,350)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 804,687 | 748,306
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (69,490) | (76,344)
Debt Securities, Available-for-sale, Unrealized Loss Position | 804,687 | 791,341
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 69,490 | $ 82,694

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