Loans - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Allowance for Credit Losses [Roll Forward]
Beginning Balance	$ 75,158	$ 43,754	$ 44,436	$ 43,765	$ 43,765
Change in Accounting Method			(7)
2/1/2025 Acquired Heartland PCD			15,908
Day 2 CECL Provision - Heartland			16,200
Provision (Benefit) for Credit Loss Expense	1,200	625	307	1,525
Loans Charged-off	(1,021)	(599)	(1,646)	(1,660)
Recoveries Collected	173	166	312	316
Total Ending Allowance Balance	75,510	43,946	75,510	43,946	44,436
Commercial and Industrial Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	15,343	7,266	7,059	7,921	7,921
Change in Accounting Method			1,438
2/1/2025 Acquired Heartland PCD			5,246
Day 2 CECL Provision - Heartland			1,797
Provision (Benefit) for Credit Loss Expense	2,620	(75)	2,545	(631)
Loans Charged-off	(247)	(29)	(373)	(131)	(223)
Recoveries Collected	23	38	27	41
Total Ending Allowance Balance	17,739	7,200	17,739	7,200	7,059
Commercial Real Estate Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	37,811	26,452	25,818	25,923	25,923
Change in Accounting Method			(3,271)
2/1/2025 Acquired Heartland PCD			7,080
Day 2 CECL Provision - Heartland			7,522
Provision (Benefit) for Credit Loss Expense	423	142	1,085	974
Loans Charged-off	(26)	0	(26)	(308)	(308)
Recoveries Collected	0	4	0	9
Total Ending Allowance Balance	38,208	26,598	38,208	26,598	25,818
Agricultural Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	5,306	3,650	4,917	3,837	3,837
Change in Accounting Method			(1,655)
2/1/2025 Acquired Heartland PCD			3,352
Day 2 CECL Provision - Heartland			170
Provision (Benefit) for Credit Loss Expense	(2,176)	46	(3,654)	(141)
Loans Charged-off	0	(1)	0	(1)	(8)
Recoveries Collected	0	2	0	2
Total Ending Allowance Balance	3,130	3,697	3,130	3,697	4,917
Leases
Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,151	373	397	346	346
Change in Accounting Method			720
2/1/2025 Acquired Heartland PCD			0
Day 2 CECL Provision - Heartland			0
Provision (Benefit) for Credit Loss Expense	41	(5)	75	22
Loans Charged-off	0	0	0	0	0
Recoveries Collected	0	0	0	0
Total Ending Allowance Balance	1,192	368	1,192	368	397
Consumer Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	657	785	727	759	759
Change in Accounting Method			(284)
2/1/2025 Acquired Heartland PCD			20
Day 2 CECL Provision - Heartland			179
Provision (Benefit) for Credit Loss Expense	259	206	486	476
Loans Charged-off	(334)	(384)	(659)	(753)	(1,511)
Recoveries Collected	109	115	222	240
Total Ending Allowance Balance	691	722	691	722	727
Home Equity Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	3,942	2,001	2,196	1,834	1,834
Change in Accounting Method			1,056
2/1/2025 Acquired Heartland PCD			11
Day 2 CECL Provision - Heartland			570
Provision (Benefit) for Credit Loss Expense	384	55	492	349
Loans Charged-off	0	0	0	(134)	(170)
Recoveries Collected	8	2	9	9
Total Ending Allowance Balance	4,334	2,058	4,334	2,058	2,196
Credit Cards
Allowance for Credit Losses [Roll Forward]
Beginning Balance	608	395	520	383	383
Change in Accounting Method			(24)
2/1/2025 Acquired Heartland PCD			0
Day 2 CECL Provision - Heartland			0
Provision (Benefit) for Credit Loss Expense	366	198	631	348
Loans Charged-off	(386)	(185)	(560)	(333)
Recoveries Collected	33	5	54	15
Total Ending Allowance Balance	621	413	621	413	520
Residential Mortgage Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	10,340	2,832	2,802	2,762	2,762
Change in Accounting Method			2,013
2/1/2025 Acquired Heartland PCD			199
Day 2 CECL Provision - Heartland			5,962
Provision (Benefit) for Credit Loss Expense	(717)	58	(1,353)	128
Loans Charged-off	(28)	0	(28)	0	0
Recoveries Collected	0	0	0	0
Total Ending Allowance Balance	$ 9,595	$ 2,890	$ 9,595	$ 2,890	$ 2,802

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable from change in methodology. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
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-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Amount, excluding accrued interest, of credit loss expense on financing receivable transferred into held-for-investment out of held-for-sale classification. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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