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Loans - Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | $ 100.3 |  | $ 107.9
Recorded Investment With No Allowance | 40.4 |  | 51.4
Recorded Investment With Allowance | 36.1 |  | 31.8
Total Recorded Investment | 76.5 |  | 83.2
Related Allowance | 10.6 |  | 10.8
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income |  |  |
Average Recorded Investment | 79.7 | $ 101.2 |
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract] |  |  |
Income Recognized | 0.0 | 0.2 |
Commercial |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 44.0 |  | 45.6
Recorded Investment With No Allowance | 17.5 |  | 20.9
Recorded Investment With Allowance | 16.1 |  | 14.1
Total Recorded Investment | 33.6 |  | 35.0
Related Allowance | 3.4 |  | 3.9
Land acquisition & development |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 9.2 |  | 10.0
Recorded Investment With No Allowance | 3.4 |  | 3.4
Recorded Investment With Allowance | 0.0 |  | 0.5
Total Recorded Investment | 3.4 |  | 3.9
Related Allowance | 0.0 |  | 0.0
Residential |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 0.8 |  | 1.8
Recorded Investment With No Allowance | 0.2 |  | 1.7
Recorded Investment With Allowance | 0.5 |  | 0.0
Total Recorded Investment | 0.7 |  | 1.7
Related Allowance | 0.1 |  | 0.0
Commercial |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 4.6 |  | 4.7
Recorded Investment With No Allowance | 0.3 |  | 0.4
Recorded Investment With Allowance | 3.4 |  | 3.5
Total Recorded Investment | 3.7 |  | 3.9
Related Allowance | 2.1 |  | 2.2
Total construction loans |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 14.6 |  | 16.5
Recorded Investment With No Allowance | 3.9 |  | 5.5
Recorded Investment With Allowance | 3.9 |  | 4.0
Total Recorded Investment | 7.8 |  | 9.5
Related Allowance | 2.2 |  | 2.2
Residential |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 9.7 |  | 11.5
Recorded Investment With No Allowance | 6.2 |  | 8.2
Recorded Investment With Allowance | 2.1 |  | 2.0
Total Recorded Investment | 8.3 |  | 10.2
Related Allowance | 0.4 |  | 0.1
Agricultural |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 4.6 |  | 3.7
Recorded Investment With No Allowance | 4.4 |  | 3.6
Recorded Investment With Allowance | 0.0 |  | 0.0
Total Recorded Investment | 4.4 |  | 3.6
Related Allowance | 0.0 |  | 0.0
Total real estate loans |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 72.9 |  | 77.3
Recorded Investment With No Allowance | 32.0 |  | 38.2
Recorded Investment With Allowance | 22.1 |  | 20.1
Total Recorded Investment | 54.1 |  | 58.3
Related Allowance | 6.0 |  | 6.2
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income |  |  |
Average Recorded Investment | 56.1 | 66.1 |
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract] |  |  |
Income Recognized | 0.0 | 0.2 |
Total consumer loans |  |  |
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income |  |  |
Average Recorded Investment | 0.0 | 0.0 |
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract] |  |  |
Income Recognized | 0.0 | 0.0 |
Commercial |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 25.4 |  | 29.5
Recorded Investment With No Allowance | 6.7 |  | 12.4
Recorded Investment With Allowance | 13.7 |  | 11.4
Total Recorded Investment | 20.4 |  | 23.8
Related Allowance | 4.5 |  | 4.4
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income |  |  |
Average Recorded Investment | 22.1 | 32.7 |
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract] |  |  |
Income Recognized | 0.0 | 0.0 |
Agricultural |  |  |
Impaired Financing Receivable, Unpaid Principal Balance |  |  |
Unpaid Total Principal Balance | 2.0 |  | 1.1
Recorded Investment With No Allowance | 1.7 |  | 0.8
Recorded Investment With Allowance | 0.3 |  | 0.3
Total Recorded Investment | 2.0 |  | 1.1
Related Allowance | 0.1 |  | $ 0.2
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income |  |  |
Average Recorded Investment | 1.5 | 2.4 |
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract] |  |  |
Income Recognized | $ 0.0 | $ 0.0 |

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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524 + Details
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- Definition Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
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