Loans - Loans Acquired (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2025	Feb. 01, 2025
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	$ 1,432,273
Loan Balance	1,432,273
Fair Value (Discount)/Premium	(54,729)
Purchase Price of Loans at Acquisition	107,285
Allowance for Credit Losses at Acquisition	16,503
Non-Credit Discount/(Premium) at Acquisition	5,554
Total	129,342
Commercial and Industrial Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	127,504
Loan Balance	127,504
Fair Value (Discount)/Premium	(3,061)
Allowance for Credit Losses at Acquisition	5,246
Commercial Real Estate Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	760,358
Loan Balance	760,358
Fair Value (Discount)/Premium	(16,134)
Allowance for Credit Losses at Acquisition	7,675
Agricultural Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	43,596
Loan Balance	43,596
Fair Value (Discount)/Premium	(640)
Allowance for Credit Losses at Acquisition	3,352
Leases
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	0
Loan Balance	0
Fair Value (Discount)/Premium	0
Allowance for Credit Losses at Acquisition	0
Consumer Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	27,187
Loan Balance	27,187
Fair Value (Discount)/Premium	(222)
Allowance for Credit Losses at Acquisition	20
Home Equity Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	57,919
Loan Balance	57,919
Fair Value (Discount)/Premium	(959)
Allowance for Credit Losses at Acquisition	11
Credit Cards
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	0
Loan Balance	0
Fair Value (Discount)/Premium	0
Allowance for Credit Losses at Acquisition	0
Residential Mortgage Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	415,709
Loan Balance	415,709
Fair Value (Discount)/Premium	(33,713)
Allowance for Credit Losses at Acquisition	$ 199
Heartland BancCorp
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance		$ 1,569,036
Fair Value Discount		(65,658)
Fair Value		1,503,378
Loan Balance		$ 1,569,036

Business Combination, Acquired Receivables, Fair Value Discounts

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Fair value of receivable purchased without credit deterioration, acquired in business combination. Excludes purchased financial asset with credit deterioration.

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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

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Amount at par value of financing receivable purchased with credit deterioration.

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Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration.

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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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