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Loans - Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2018
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance | $ 5.8 |  | $ 5.8 |  |  | $ 0.3 |  |
Impaired Financing Receivable, Related Allowance |  |  |  |  |  | 3.6 |  |
Provision charged to operating expense | (19.5) | $ (3.8) | (48.5) | $ (7.5) |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 146.1 | $ 74.2 | 146.1 | $ 74.2 | $ 129.1 | 73.0 | $ 72.4 | $ 73.0
Collateral dependent borrowings | 12.5 |  | 12.5 |  |  |  |  |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 19.3 |  |  |  |  |  |  |
Agriculture Portfolio Segment [Member] |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Provision charged to operating expense | (0.1) |  |  |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 0.9 |  | 0.9 |  | 1.1 |  |  |
Total real estate loans |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Provision charged to operating expense | (10.0) |  | (18.1) |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 75.2 |  | 75.2 |  | 65.0 | 28.9 |  |
Collateral dependent borrowings | 0.9 |  | 0.9 |  |  |  |  |
Commercial |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Provision charged to operating expense | (8.6) |  | (24.9) |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 46.5 |  | 46.5 |  | 38.2 | 32.6 |  |
Collateral dependent borrowings | 11.5 |  | 11.5 |  |  |  |  |
Agricultural |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Provision charged to operating expense | (0.1) |  | 0.0 |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 0.9 |  | 0.9 |  | $ 1.1 | $ 1.6 |  |
Collateral dependent borrowings | 0.1 |  | 0.1 |  |  |  |  |
Business Assets Pledged as Collateral [Member] |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 5.8 |  | 5.8 |  |  |  |  |
Business Assets Pledged as Collateral [Member] | Total real estate loans |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.3 |  | 0.3 |  |  |  |  |
Business Assets Pledged as Collateral [Member] | Commercial |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 5.5 |  | 5.5 |  |  |  |  |
Business Assets Pledged as Collateral [Member] | Agricultural |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.0 |  | 0.0 |  |  |  |  |
Real Property Pledged as Collateral [Member] |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 6.2 |  | 6.2 |  |  |  |  |
Real Property Pledged as Collateral [Member] | Total real estate loans |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.6 |  | 0.6 |  |  |  |  |
Real Property Pledged as Collateral [Member] | Commercial |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 5.5 |  | 5.5 |  |  |  |  |
Real Property Pledged as Collateral [Member] | Agricultural |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.1 |  | 0.1 |  |  |  |  |
Other Property [Member] |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.5 |  | 0.5 |  |  |  |  |
Other Property [Member] | Total real estate loans |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.0 |  | 0.0 |  |  |  |  |
Other Property [Member] | Commercial |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | 0.5 |  | 0.5 |  |  |  |  |
Other Property [Member] | Agricultural |  |  |  |  |  |  |  |
Loans and Leases Receivable Recorded Investment, Impaired [Line Items] |  |  |  |  |  |  |  |
Collateral dependent borrowings | $ 0.0 |  | $ 0.0 |  |  |  |  |

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- Definition Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5086-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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