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Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Entity Information |  |  |
Unused credit card lines |  | $ 2,539.8 |
Off-Balance Sheet, Credit Loss, Liability | $ 16.2 | 3.8 | $ 3.7
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | (68.4) | 14.7 | $ (55.5)
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Entity Information |  |  |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 12.4 | 0.1 |
Unused Credit Card Lines |  |  |
Entity Information |  |  |
Credit extension commitments | 827.6 | 681.6 |
Unused credit card lines | 5,173.3 |  |
Standby Letters of Credit |  |  |
Entity Information |  |  |
Credit extension commitments | $ 93.8 | $ 57.5 |

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- Definition Credit Extension Commitments + References No definition available. + Details
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- Definition Credit Extension Commitments, Beyond One Year + 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=124255206&loc=SL82919202-210446 + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. 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 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
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- Details
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