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Loans and Allowance for Credit Losses - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($) commitment loan	Jun. 30, 2024 USD ($) commitment	Jun. 30, 2025 USD ($) loan commitment	Jun. 30, 2024 USD ($) commitment	Dec. 31, 2024 USD ($)
Receivables [Abstract]
Unearned income	$ 4.4		$ 4.4		$ 4.3
Purchase accounting fair value adjustments	$ 2.2		$ 2.2		$ 2.5
Number of subsequent payment defaults | loan	1		2
Amount of defaulted TDRs that defaulted	$ 0.1	$ 0.0	$ 3.9	$ 0.0
Number of commitments to lend | commitment	11	3	11	3
Commitment to lend	$ 0.1	$ 1.2	$ 0.1	$ 1.2

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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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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Amount of unamortized purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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