Allowance for Credit Losses (Accrued Interest) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Receivables [Abstract]
Loans	$ 210.8	$ 203.1
Debt Securities
Held to Maturity	66.0	63.2
Available for Sale	136.5	147.1
Other Financial Assets	59.0	43.8
Total	$ 472.3	$ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 3B
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267856-210455

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5C
-URI https://asc.fasb.org/extlink&oid=126970911&loc=SL121698325-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 3A
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3A
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267960-210447

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL120267845-210446

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
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- References

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