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Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Millions | Jun. 30, 2020 | Mar. 31, 2020 | Mar. 01, 2020 | Jan. 01, 2020 | Dec. 31, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | --- | --- | --- | --- | ---
Entity Information [Line Items] |  |  |  |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | $ 146.1 | $ 129.1 |  |  | $ 73.0 | $ 74.2 | $ 72.4 | $ 73.0
Off-Balance Sheet, Credit Loss, Liability |  |  |  |  | 0.0 |  |  |
Credit Extension Commitments | 2,228.8 |  |  |  | 2,067.0 |  |  |
Unused Credit Card Lines |  |  |  |  |  |  |  |
Entity Information [Line Items] |  |  |  |  |  |  |  |
Credit Extension Commitments | 692.5 |  |  |  | 671.8 |  |  |
Standby Letter of Credit |  |  |  |  |  |  |  |
Entity Information [Line Items] |  |  |  |  |  |  |  |
Credit Extension Commitments | 55.7 |  |  |  | 42.7 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] |  |  |  |  |  |  |  |
Entity Information [Line Items] |  |  |  |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss |  | 2.1 |  | $ 103.0 | 0.0 |  | 0.0 | 0.0
Off-Balance Sheet, Credit Loss, Liability | 2.3 | 0.2 | $ 0.0 | 2.3 | 0.0 | $ 0.0 | $ 0.0 | $ 0.0
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |  |  |
Entity Information [Line Items] |  |  |  |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 30.0 |  |  | 30.0 |  |  |  |
Off-Balance Sheet, Credit Loss, Liability |  |  |  | $ 2.3 |  |  |  |
Agricultural |  |  |  |  |  |  |  |
Entity Information [Line Items] |  |  |  |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 0.9 | $ 1.1 |  |  | $ 1.6 |  |  |
Agricultural | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |  |  |
Entity Information [Line Items] |  |  |  |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | $ (0.6) |  |  |  |  |  |  |

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- Definition Amount of allowance for credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 + Details
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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121611286&loc=d3e11927-110247 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82919202-210446 + Details
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