Allowance for Credit Losses (Accrued Interest) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Receivables [Abstract]
Loans	$ 220.2	$ 241.7
Debt Securities
Held to Maturity	75.1	72.0
Available for Sale	177.2	129.2
Other Financial Assets	79.2	86.0
Total	$ 551.7	$ 528.9

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
-Section 50
-Paragraph 2A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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
-Section 50
-Paragraph 5C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5C

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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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
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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-URI https://asc.fasb.org/1943274/2147479344/326-20-45-5

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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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-SubTopic 310
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-Topic 210
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- References

No definition available.

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