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Loans - Schedule of Recorded Investment in Past Due Loans by Class (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Loans and Leases Receivable Recorded Investment, Past Due |  |
Total loans | $ 9,331.7 | $ 9,807.5
Impaired Financing Receivable, Interest Income, Accrual Method | 0.0 | 0.3
Financing Receivable, Allowance for Credit Loss, Writeoff | 16.6 | 20.9
Loans and Leases Receivable, Nonperforming, Accrual of Interest | 0.0 |
Financing Receivable, Accrued Interest, Writeoff | 0.0 |
Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 8.0 | 9.6
Loans held for investment | 3,971.5 | 3,743.2
Financing Receivable, Allowance for Credit Loss, Writeoff | 2.3 | 0.4
Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.7 | 0.7
Loans held for investment | 247.8 | 265.0
Total loans | 247.8 | 265.0
Financing Receivable, Allowance for Credit Loss, Writeoff | 1.2 | 0.5
Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.0 | 1.1
Loans held for investment | 262.0 | 250.9
Total loans | 262.0 | 250.9
Financing Receivable, Allowance for Credit Loss, Writeoff | 0.1 | 0.0
Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.0 | 0.1
Loans held for investment | 498.0 | 523.5
Total loans | 498.0 | 523.5
Financing Receivable, Allowance for Credit Loss, Writeoff | 0.1 | 0.0
Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.7 | 1.9
Loans held for investment | 1,007.8 | 1,039.4
Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 2.9 | 4.6
Loans held for investment | 1,538.2 | 1,396.3
Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 4.9 | 6.2
Loans held for investment | 213.9 | 220.6
Total loans | 213.9 | 220.6
Financing Receivable, Allowance for Credit Loss, Writeoff | 0.7 | 0.0
Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 16.5 | 22.3
Loans held for investment | 6,731.4 | 6,399.5
Impaired Financing Receivable, Interest Income, Accrual Method |  | 0.1
Financing Receivable, Allowance for Credit Loss, Writeoff | 4.5 | 0.9
Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 1.7 | 1.9
Loans held for investment | 737.6 | 805.1
Total loans | 737.6 | 805.1
Financing Receivable, Allowance for Credit Loss, Writeoff | 3.5 | 4.1
Other consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.1 | 0.4
Loans held for investment | 129.2 | 150.6
Total loans | 129.2 | 150.6
Financing Receivable, Allowance for Credit Loss, Writeoff | 2.9 | 3.9
Credit card consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.0 | 0.0
Loans held for investment | 64.9 | 70.2
Financing Receivable, Allowance for Credit Loss, Writeoff | 1.8 | 2.8
Total consumer loans |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 1.8 | 2.3
Loans held for investment | 931.7 | 1,025.9
Financing Receivable, Allowance for Credit Loss, Writeoff | 8.2 | 10.8
Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 5.0 | 11.8
Loans held for investment | 1,475.5 | 2,153.9
Impaired Financing Receivable, Interest Income, Accrual Method |  | 0.2
Financing Receivable, Allowance for Credit Loss, Writeoff | 3.7 | 9.1
Other, including overdrafts |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 0.0 | 0.0
Loans held for investment | 1.5 | 1.6
Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 24.9 | 39.5
Loans held for investment | 9,344.0 | 9,828.5
Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Non-accrual Loans | 1.6 | 3.1
Loans held for investment | 203.9 | 247.6
Financing Receivable, Allowance for Credit Loss, Writeoff | 0.2 | 0.1
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.1 | 7.6
Financing Receivables, 30 to 59 Days Past Due | Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.2 | 2.5
Financing Receivables, 30 to 59 Days Past Due | Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 4.2 | 1.5
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 12.2
Financing Receivables, 30 to 59 Days Past Due | Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 4.4 | 16.2
Financing Receivables, 30 to 59 Days Past Due | Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 3.0 | 4.7
Financing Receivables, 30 to 59 Days Past Due | Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.9 | 2.0
Financing Receivables, 30 to 59 Days Past Due | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 10.4 | 30.5
Financing Receivables, 30 to 59 Days Past Due | Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 5.1 | 6.4
Financing Receivables, 30 to 59 Days Past Due | Other consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.5 | 0.8
Financing Receivables, 30 to 59 Days Past Due | Credit card consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.6 | 0.6
Financing Receivables, 30 to 59 Days Past Due | Total consumer loans |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 6.2 | 7.8
Financing Receivables, 30 to 59 Days Past Due | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 4.9 | 6.2
Financing Receivables, 30 to 59 Days Past Due | Other, including overdrafts |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, 30 to 59 Days Past Due | Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 22.2 | 44.9
Financing Receivables, 30 to 59 Days Past Due | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.7 | 0.4
Financing Receivables, 60 to 89 Days Past Due | Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.0 | 1.2
Financing Receivables, 60 to 89 Days Past Due | Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 1.1
Financing Receivables, 60 to 89 Days Past Due | Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.4
Financing Receivables, 60 to 89 Days Past Due | Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, 60 to 89 Days Past Due | Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 1.5
Financing Receivables, 60 to 89 Days Past Due | Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.8 | 1.6
Financing Receivables, 60 to 89 Days Past Due | Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.2 | 0.0
Financing Receivables, 60 to 89 Days Past Due | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 2.0 | 4.3
Financing Receivables, 60 to 89 Days Past Due | Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.4 | 2.0
Financing Receivables, 60 to 89 Days Past Due | Other consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.2 | 0.2
Financing Receivables, 60 to 89 Days Past Due | Credit card consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.2 | 0.4
Financing Receivables, 60 to 89 Days Past Due | Total consumer loans |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.8 | 2.6
Financing Receivables, 60 to 89 Days Past Due | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.7 | 1.8
Financing Receivables, 60 to 89 Days Past Due | Other, including overdrafts |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, 60 to 89 Days Past Due | Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 4.5 | 9.3
Financing Receivables, 60 to 89 Days Past Due | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.6
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.6 | 4.0
Financing Receivables, Equal to Greater than 90 Days Past Due | Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.1
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, Equal to Greater than 90 Days Past Due | Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.1
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.1 | 0.5
Financing Receivables, Equal to Greater than 90 Days Past Due | Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, Equal to Greater than 90 Days Past Due | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.7 | 4.6
Financing Receivables, Equal to Greater than 90 Days Past Due | Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.4 | 0.5
Financing Receivables, Equal to Greater than 90 Days Past Due | Other consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.1 | 0.2
Financing Receivables, Equal to Greater than 90 Days Past Due | Credit card consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.5 | 0.6
Financing Receivables, Equal to Greater than 90 Days Past Due | Total consumer loans |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.0 | 1.3
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.1 | 1.2
Financing Receivables, Equal to Greater than 90 Days Past Due | Other, including overdrafts |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financing Receivables, Equal to Greater than 90 Days Past Due | Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 2.8 | 8.5
Financing Receivables, Equal to Greater than 90 Days Past Due | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 1.4
Financial Asset, Past Due | Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 2.7 | 12.8
Financial Asset, Past Due | Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.2 | 3.7
Financial Asset, Past Due | Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 4.2 | 1.9
Financial Asset, Past Due | Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 12.2
Financial Asset, Past Due | Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 4.4 | 17.8
Financial Asset, Past Due | Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 3.9 | 6.8
Financial Asset, Past Due | Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 2.1 | 2.0
Financial Asset, Past Due | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 13.1 | 39.4
Financial Asset, Past Due | Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 6.9 | 8.9
Financial Asset, Past Due | Other consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.8 | 1.2
Financial Asset, Past Due | Credit card consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.3 | 1.6
Financial Asset, Past Due | Total consumer loans |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 9.0 | 11.7
Financial Asset, Past Due | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 6.7 | 9.2
Financial Asset, Past Due | Other, including overdrafts |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.0 | 0.0
Financial Asset, Past Due | Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 29.5 | 62.7
Financial Asset, Past Due | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 0.7 | 2.4
Financial Asset, Not Past Due | Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 3,960.8 | 3,720.8
Financial Asset, Not Past Due | Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 246.9 | 260.6
Financial Asset, Not Past Due | Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 257.8 | 247.9
Financial Asset, Not Past Due | Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 498.0 | 511.2
Financial Asset, Not Past Due | Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1,002.7 | 1,019.7
Financial Asset, Not Past Due | Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1,531.4 | 1,384.9
Financial Asset, Not Past Due | Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 206.9 | 212.4
Financial Asset, Not Past Due | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 6,701.8 | 6,337.8
Financial Asset, Not Past Due | Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 729.0 | 794.3
Financial Asset, Not Past Due | Other consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 128.3 | 149.0
Financial Asset, Not Past Due | Credit card consumer |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 63.6 | 68.6
Financial Asset, Not Past Due | Total consumer loans |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 920.9 | 1,011.9
Financial Asset, Not Past Due | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1,463.8 | 2,132.9
Financial Asset, Not Past Due | Other, including overdrafts |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 1.5 | 1.6
Financial Asset, Not Past Due | Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | 9,289.6 | 9,726.3
Financial Asset, Not Past Due | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Past Due |  |
Financing Receivable, Loan in Process | $ 201.6 | $ 242.1

X
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
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- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522 + Details
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