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Loans - Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |
Loans and Leases Receivable, Impaired, Troubled Debt, Interest Income | $ 3.0 | $ 3.5 | $ 4.2
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 83.0 | 107.9 | 132.8
Recorded Investment With No Allowance | 36.0 | 51.4 | 57.9
Recorded Investment With Allowance | 28.8 | 31.8 | 46.8
Total Recorded Investment | 64.8 | 83.2 | 104.7
Related Allowance | 6.8 | 10.8 | 14.0
Average Recorded Investment | 74.0 | 94.0 | 101.1
Income Recognized | 0.3 | 0.5 | 0.6
Impaired Loans, interest lost on nonaccrual loans |  |  | 3.4
Commercial |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 22.2 | 45.6 | 57.0
Recorded Investment With No Allowance | 8.6 | 20.9 | 24.4
Recorded Investment With Allowance | 7.7 | 14.1 | 21.4
Total Recorded Investment | 16.3 | 35.0 | 45.8
Related Allowance | 0.7 | 3.9 | 2.8
Land acquisition & development |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 10.0 | 10.0 | 12.1
Recorded Investment With No Allowance | 0.4 | 3.4 | 4.3
Recorded Investment With Allowance | 3.5 | 0.5 | 1.8
Total Recorded Investment | 3.9 | 3.9 | 6.1
Related Allowance | 0.2 | 0.0 | 0.8
Residential |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 1.1 | 1.8 | 1.6
Recorded Investment With No Allowance | 0.6 | 1.7 | 0.2
Recorded Investment With Allowance | 0.4 | 0.0 | 0.6
Total Recorded Investment | 1.0 | 1.7 | 0.8
Related Allowance | 0.1 | 0.0 | 0.0
Commercial |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 0.7 | 4.7 | 4.8
Recorded Investment With No Allowance | 0.2 | 0.4 | 3.9
Recorded Investment With Allowance | 0.0 | 3.5 | 0.7
Total Recorded Investment | 0.2 | 3.9 | 4.6
Related Allowance | 0.0 | 2.2 | 0.7
Total construction loans |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 11.8 | 16.5 | 18.5
Recorded Investment With No Allowance | 1.2 | 5.5 | 8.4
Recorded Investment With Allowance | 3.9 | 4.0 | 3.1
Total Recorded Investment | 5.1 | 9.5 | 11.5
Related Allowance | 0.3 | 2.2 | 1.5
Residential |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 8.8 | 11.5 | 8.2
Recorded Investment With No Allowance | 5.7 | 8.2 | 4.1
Recorded Investment With Allowance | 2.0 | 2.0 | 2.5
Total Recorded Investment | 7.7 | 10.2 | 6.6
Related Allowance | 0.3 | 0.1 | 0.3
Agricultural |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 12.9 | 3.7 | 5.1
Recorded Investment With No Allowance | 12.5 | 3.6 | 4.5
Recorded Investment With Allowance | 0.2 | 0.0 | 0.2
Total Recorded Investment | 12.7 | 3.6 | 4.7
Related Allowance | 0.0 | 0.0 | 0.0
Total real estate loans |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 55.7 | 77.3 | 88.8
Recorded Investment With No Allowance | 28.0 | 38.2 | 41.4
Recorded Investment With Allowance | 13.8 | 20.1 | 27.2
Total Recorded Investment | 41.8 | 58.3 | 68.6
Related Allowance | 1.3 | 6.2 | 4.6
Average Recorded Investment | 50.0 | 63.5 | 69.2
Income Recognized | 0.1 | 0.3 | 0.3
Commercial |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 24.1 | 29.5 | 40.3
Recorded Investment With No Allowance | 5.5 | 12.4 | 13.2
Recorded Investment With Allowance | 14.4 | 11.4 | 19.2
Total Recorded Investment | 19.9 | 23.8 | 32.4
Related Allowance | 5.2 | 4.4 | 9.3
Average Recorded Investment | 21.9 | 28.1 | 30.1
Income Recognized | 0.2 | 0.2 | 0.3
Agricultural |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 3.2 | 1.1 | 3.7
Recorded Investment With No Allowance | 2.5 | 0.8 | 3.3
Recorded Investment With Allowance | 0.6 | 0.3 | 0.4
Total Recorded Investment | 3.1 | 1.1 | 3.7
Related Allowance | 0.3 | 0.2 | 0.1
Average Recorded Investment | 2.1 | 2.4 | 1.8
Income Recognized | $ 0.0 | $ 0.0 | $ 0.0

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