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Loans (Analysis of Nonaccrual Loans with no ACL) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Financing Receivable, Nonaccrual [Line Items] |  |
Amortized Cost of Nonaccrual Loans, No Allowance | $ 20,911 | $ 19,275
Commercial Real Estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Amortized Cost of Nonaccrual Loans, No Allowance | 6,393 | 1,715
Commercial Business |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Amortized Cost of Nonaccrual Loans, No Allowance | 6,382 | 15,762
Agriculture |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Amortized Cost of Nonaccrual Loans, No Allowance | $ 8,136 | $ 1,798

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