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Loans - Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Commercial Real Estate Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | $ 8,528.6 | $ 3,971.5
Land Acquisition And Development Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 386.2 | 247.8
Residential Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 516.2 | 262.0
Commercial Real Estate Construction [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 1,042.0 | 498.0
Real Estate Construction Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 1,944.4 | 1,007.8
Residential Mortgage [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 2,188.3 | 1,538.2
Agricultural Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 794.9 | 213.9
Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 13,456.2 | 6,731.4
Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 708.3 | 203.9
Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 2,882.6 | 1,475.5
Loans held for investment |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 18,114.8 | 9,344.0
Indirect consumer |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 829.7 | 737.6
Other consumer |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 152.9 | 129.2
Collateral |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 39.1 | 11.7
Collateral | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 27.2 | 8.2
Collateral | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 7.3 | 0.7
Collateral | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 4.6 | 2.8
Business Assets Pledged as Collateral | Collateral |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 7.1 | 3.0
Business Assets Pledged as Collateral | Collateral | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 1.9 | 1.2
Business Assets Pledged as Collateral | Collateral | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 2.1 | 0.0
Business Assets Pledged as Collateral | Collateral | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 3.1 | 1.8
Real Property Pledged as Collateral | Collateral |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 32.0 | 8.7
Real Property Pledged as Collateral | Collateral | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 25.3 | 7.0
Real Property Pledged as Collateral | Collateral | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 5.2 | 0.7
Real Property Pledged as Collateral | Collateral | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 1.5 | 1.0
Other Property | Collateral |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 0.0 | 0.0
Other Property | Collateral | Real Estate Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 0.0 | 0.0
Other Property | Collateral | Agricultural Financing Receivable [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | 0.0 | 0.0
Other Property | Collateral | Commercial Portfolio Segment [Member] |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |
Loans and Leases Receivable, Collateral for Secured Borrowings | $ 0.0 | $ 0.0

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