Loans - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Schedule of Loans by Loan Classification [Line Items]
Loan origination fees	$ 4.4	$ 5.4
Accrued interest receivable on loans	$ 17.3	$ 16.1
Accrued interest, statement of financial position	Accrued interest receivable	Accrued interest receivable
Commercial
Schedule of Loans by Loan Classification [Line Items]
Participation loans amount	$ 148.1	$ 126.6
Participations loans sold that are still serviced amount	73.0	69.8
Residential mortgages
Schedule of Loans by Loan Classification [Line Items]
Amount of loans serviced for others	$ 7.4	$ 7.7

Participation Loans, Amount of Participations Purchased

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Participations Loans Sold, Serviced Amount

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Schedule of Loans by Loan Classification [Line Items]

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

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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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