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Loans and Allowance for Credit Losses - Loans by Type as Percentage of Portfolio (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Jun. 30, 2025	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 2,909,928	$ 1,545,640
Allowance for credit loss	$ 34,754	$ 16,552	$ 34,798	$ 16,490	$ 16,152	$ 15,685
Percentage of allowance for credit losses	1.19%	1.07%
Loans, net	$ 2,875,174	$ 1,529,088
Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 51,183	$ 48,221
Percentage of loans	1.80%	3.10%
Percentage of increase decrease of loans	6.10%
Allowance for credit loss	$ 233	$ 90	219	110	112	94
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 352,876	$ 228,256
Percentage of loans	12.10%	14.80%
Percentage of increase decrease of loans	54.60%
Allowance for credit loss	$ 6,297	$ 2,260	5,240	2,470	2,161	2,216
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 1,728,774	$ 901,130
Percentage of loans	59.40%	58.30%
Percentage of increase decrease of loans	91.80%
Allowance for credit loss	$ 17,575	$ 9,460	18,311	9,220	9,360	8,820
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 27,328	$ 29,412
Percentage of loans	0.90%	1.90%
Percentage of increase decrease of loans	(7.10%)
Allowance for credit loss	$ 736	$ 733	772	761	795	823
Construction Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 18,441	$ 17,042
Percentage of loans	0.60%	1.10%
Percentage of increase decrease of loans	8.20%
Allowance for credit loss	$ 83	$ 59	90	36	49	58
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 728,843	$ 281,701
Percentage of loans	25.00%	18.20%
Percentage of increase decrease of loans	158.70%
Allowance for credit loss	$ 9,826	$ 3,890	10,161	3,833	3,625	3,644
Loans to other financial institutions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 2,483	$ 39,878
Percentage of loans	0.10%	2.60%
Percentage of increase decrease of loans	(93.80%)
Allowance for credit loss	$ 4	$ 60	$ 5	$ 60	$ 50	$ 30

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