Allowance for Credit Losses (Accrued Interest) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Receivables [Abstract]
Loans	$ 183.4	$ 184.6
Debt Securities
Held to Maturity	85.1	76.9
Available for Sale	205.3	175.0
Other Financial Assets	61.9	62.2
Total	$ 535.7	$ 498.7

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.

+ Details

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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
-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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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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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

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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
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477802/946-310-45-1

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- References

No definition available.

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