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Loans Held for Investment - Schedule of Troubled Debt Restructurings (Details) | 12 Months Ended
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Dec. 31, 2022 USD ($) note | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Loans renegotiated in troubled debt restructurings | $ 64,600,000 | $ 6,200,000 |
Loans renegotiated in troubled debt restructurings, non-accrual loans | 4,200,000 | 3,900,000 |
Loans renegotiated in troubled debt restructurings, accrual loans | $ 60,400,000 | 2,300,000 |
Number of notes under troubled debt restructurings | note | 12 |  |
Charge-offs directly related to modified loans | $ 5,700,000 | $ 0 | $ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification | 71,700,000 |  |
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend | 0 |  |
Balance of notes for which there was a payment default | 0 |  |
Impaired Financing Receivable, Recorded Investment | 743,300,000 |  |
Financing Receivable, Allowance for Credit Loss, Noncurrent | $ 100,000 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Number of notes under troubled debt restructurings | note | 4 |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 53,700,000 |  |
Agricultural Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Number of notes under troubled debt restructurings | note | 2 |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 9,000,000.0 |  |
Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Number of notes under troubled debt restructurings | note | 3 |  |
Concessions in troubled debt restructurings, amount | $ 2,500,000 |  |
Agriculture |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Number of notes under troubled debt restructurings | note | 1 |  |
Concessions in troubled debt restructurings, amount | $ 5,900,000 |  |
Residential Real Estate |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Number of notes under troubled debt restructurings | note | 2 |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 600,000 |  |
Interest Only Period Concession |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 3,200,000 |  |
Interest Only Period Concession | Commercial Real Estate Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 3,200,000 |  |
Interest Only Period Concession | Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 0 |  |
Interest Only Period Concession | Agriculture |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 0 |  |
Extension of terms or maturity |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 15,700,000 |  |
Extension of terms or maturity | Commercial Real Estate Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 4,200,000 |  |
Extension of terms or maturity | Agricultural Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 9,000,000.0 |  |
Extension of terms or maturity | Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 1,900,000 |  |
Extension of terms or maturity | Agriculture |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 0 |  |
Extension of terms or maturity | Residential Real Estate |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 600,000 |  |
Interest rate adjustment |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 0 |  |
Interest rate adjustment | Commercial Real Estate Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 0 |  |
Interest rate adjustment | Agricultural Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 0 |  |
Interest rate adjustment | Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 0 |  |
Interest rate adjustment | Agriculture |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 0 |  |
Interest rate adjustment | Residential Real Estate |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 0 |  |
Other |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 52,800,000 |  |
Other | Commercial Real Estate Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 46,300,000 |  |
Other | Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 600,000 |  |
Other | Agriculture |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 5,900,000 |  |
Interest Only Period | Agricultural Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 0 |  |
Interest Only Period | Residential Real Estate |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Concessions in troubled debt restructurings, amount | 0 |  |
Other Loan Restructuring Modification | Agricultural Real Estate Financing Receivable [Member] |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | 0 |  |
Other Loan Restructuring Modification | Residential Real Estate |  |  |
Loans and Leases Receivable, Troubled Debt Restructuring |  |  |
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 0 |  |

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