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Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Millions | Mar. 31, 2020 | Jan. 01, 2020 | Dec. 31, 2019 | Mar. 31, 2019
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Entity Information [Line Items] |  |  |  |
Off-Balance Sheet, Credit Loss, Liability | $ (2.1) | $ (0.2) | $ 0.0 | $ 0.0
Credit Extension Commitments | 2,122.4 |  | 2,067.0 |
Unused Credit Card Lines |  |  |  |
Entity Information [Line Items] |  |  |  |
Credit Extension Commitments | 1,480.5 |  | 1,450.5 |
Standby Letter of Credit |  |  |  |
Entity Information [Line Items] |  |  |  |
Credit Extension Commitments | $ 56.2 |  | $ 42.7 |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |
Entity Information [Line Items] |  |  |  |
Off-Balance Sheet, Credit Loss, Liability |  | $ (2.3) |  | $ 0.0

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Credit Extension Commitments + References No definition available. + 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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- Details
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- Details
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- Details
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Balance Type: |
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