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Loans and Allowance for Credit Losses - Narrative (Details) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2024 USD ($) loan numberOfDefault	Dec. 31, 2023 USD ($) numberOfDefault loan	Dec. 31, 2024 USD ($) loan numberOfDefault	Dec. 31, 2023 USD ($) loan numberOfDefault
Receivables [Abstract]
Unearned income	$ 4.3	$ 6.6	$ 4.3	$ 6.6
Purchase accounting fair value adjustments	$ 2.5	$ 3.1	$ 2.5	$ 3.1
Financing receivable, modified, number of subsequent payment defaults | numberOfDefault	1	0	1	0
Amount of defaulted TDRs that were restructured within the last twelve months prior to defaulting	$ 0.1		$ 0.1
Number of commitments to lend | loan	5	3	5	3
Financing receivable, modified, commitment to lend	$ 0.8	$ 1.6	$ 0.8	$ 1.6

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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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