v3.21.1

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Concentration Risk [Line Items] |  |  |
Off-balance sheet, credit loss, liability | $ 3.9 |  | $ 4.1
Credit loss expense, off balance sheet credit exposure | $ (0.2) | $ 2.4 |
Credit Concentration Risk | Loans Concentration | Commercial real estate |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 60.00% |  |
Credit Concentration Risk | Loans Concentration | Agricultural Related Loan Financing Receivable |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 8.00% |  |
Credit Concentration Risk | Investment Securities | State and political subdivisions | IOWA |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 20.00% |  |
Credit Concentration Risk | Investment Securities | State and political subdivisions | MINNESOTA |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 14.00% |  |

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