v3.25.3

Allowance for Credit Losses (Changes in Allowance for Credit Losses Related to Loans) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
LOANS
Balance at Beginning of Period	$ 180.5	$ 167.7	$ 168.0	$ 178.7	$ 178.7
Charge-Offs	(2.1)	0.0	(2.5)	(11.4)	(15.5)
Recoveries	1.7	2.4	2.6	3.5
Net Recoveries (Charge-Offs)	(0.4)	2.4	0.1	(7.9)
Provision for Credit Losses	(15.7)	14.7	(3.7)	14.0
Balance at End of Period	164.4	184.8	164.4	184.8	168.0
UNDRAWN LOAN COMMITMENTS AND STANDBY LETTERS OF CREDIT
Balance at Beginning of Period	34.7	29.5	30.4	26.9	26.9
Charge-Offs	0.0	0.0	0.0	0.0
Recoveries	0.0	0.0	0.0	0.0
Net Recoveries (Charge-Offs)	0.0	0.0	0.0	0.0
Provision for Credit Losses	(2.6)	(3.0)	1.7	(0.4)
Balance at End of Period	32.1	26.5	32.1	26.5	30.4
COMMERCIAL
LOANS
Balance at Beginning of Period	145.8	136.9	138.5	146.8	146.8
Charge-Offs	(2.0)	0.0	(2.3)	(11.0)	(15.1)
Recoveries	1.3	0.0	1.4	0.0
Net Recoveries (Charge-Offs)	(0.7)	0.0	(0.9)	(11.0)
Provision for Credit Losses	(11.2)	15.7	(3.7)	16.8
Balance at End of Period	133.9	152.6	133.9	152.6	138.5
UNDRAWN LOAN COMMITMENTS AND STANDBY LETTERS OF CREDIT
Balance at Beginning of Period	32.5	27.2	28.3	24.9	24.9
Charge-Offs	0.0	0.0	0.0	0.0
Recoveries	0.0	0.0	0.0	0.0
Net Recoveries (Charge-Offs)	0.0	0.0	0.0	0.0
Provision for Credit Losses	(2.6)	(2.7)	1.6	(0.4)
Balance at End of Period	29.9	24.5	29.9	24.5	28.3
PERSONAL
LOANS
Balance at Beginning of Period	34.7	30.8	29.5	31.9	31.9
Charge-Offs	(0.1)	0.0	(0.2)	(0.4)	(0.4)
Recoveries	0.4	2.4	1.2	3.5
Net Recoveries (Charge-Offs)	0.3	2.4	1.0	3.1
Provision for Credit Losses	(4.5)	(1.0)	0.0	(2.8)
Balance at End of Period	30.5	32.2	30.5	32.2	29.5
UNDRAWN LOAN COMMITMENTS AND STANDBY LETTERS OF CREDIT
Balance at Beginning of Period	2.2	2.3	2.1	2.0	2.0
Charge-Offs	0.0	0.0	0.0	0.0
Recoveries	0.0	0.0	0.0	0.0
Net Recoveries (Charge-Offs)	0.0	0.0	0.0	0.0
Provision for Credit Losses	0.0	(0.3)	0.1	0.0
Balance at End of Period	$ 2.2	$ 2.0	$ 2.2	$ 2.0	$ 2.1

Off Balance Sheet, Allowance For Credit Loss, Writeoff

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Off-Balance Sheet, Credit Loss, Liability, Change in Present Value, Expense (Reversal)

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Off-Balance Sheet, Credit Loss, Liability, Recovery

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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-Publisher FASB
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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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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.

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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.

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