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Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands | Mar. 31, 2021 USD ($) holding | Dec. 31, 2020 USD ($) 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 | 15 | 7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 221,563 | $ 24,248
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (6,153) | (89)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,552 | 1,056
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (349) | (373)
Debt Securities, Available-for-sale, Unrealized Loss Position | 223,115 | 25,304
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 6,502 | $ 462
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 | 8 | 3
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 98,873 | $ 437
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (3,898) | (1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position | 98,873 | 437
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 3,898 | $ 1
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 | 1 | 2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 9,519 | $ 23,323
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (11) | (87)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position | 9,519 | 23,323
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 11 | $ 87
Single issuer 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 | $ 488
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | (1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 488 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (1) | 0
Debt Securities, Available-for-sale, Unrealized Loss Position | 488 | 488
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 1 | $ 1
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 | 1,064 | 1,056
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (348) | (373)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,064 | 1,056
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 348 | $ 373
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 | 4 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 113,171 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (2,244) |
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 | 113,171 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 2,244 |

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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