Allowance for Credit Losses (Accrued Interest) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Receivables [Abstract]
Loans	$ 249.4	$ 203.1
Debt Securities
Held to Maturity	82.7	63.2
Available for Sale	138.0	147.1
Other Financial Assets	58.4	43.8
Total	$ 528.5	$ 457.2

Debt Securities, Accrued Interest, After Allowance For Credit Loss

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- Definition

Other Financial Assets, Accrued Interest, After Allowance For Credit Loss

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 2A
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- Definition

Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5C

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 45
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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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