Loans - Loans Acquired (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2025	Feb. 01, 2025
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	$ 1,466,891
Loan Balance	1,466,891
Fair Value (Discount)/Premium	(58,444)
Purchase Price of Loans at Acquisition	94,387
Allowance for Credit Losses at Acquisition	15,908
Non-Credit Discount/(Premium) at Acquisition	6,449
Total	116,744
Commercial and Industrial Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	132,016
Loan Balance	132,016
Fair Value (Discount)/Premium	(3,395)
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	782,537
Loan Balance	782,537
Fair Value (Discount)/Premium	(17,950)
Allowance for Credit Losses at Acquisition	7,080
Agricultural Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loan Balance	35,622
Loan Balance	35,622
Fair Value (Discount)/Premium	(649)
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	26,813
Loan Balance	26,813
Fair Value (Discount)/Premium	(317)
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	58,589
Loan Balance	58,589
Fair Value (Discount)/Premium	(1,009)
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	431,314
Loan Balance	431,314
Fair Value (Discount)/Premium	(35,124)
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		$ 1,569,631
Fair Value Discount		(65,658)
Fair Value		1,503,973
Loan Balance		$ 1,569,631

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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