Business Combinations - Information about Loans Acquired (Details) - Frontier [Member] $ in Thousands	Jan. 01, 2026 USD ($)
Business Combination [Line Items]
Fair value of acquired loans	$ 1,276,668
Purchased Seasoned Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	1,249,777
Purchased Seasoned Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	724,286
Purchased Seasoned Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	150,209
Purchased Seasoned Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	129,230
Purchased Seasoned Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	160,750
Purchased Seasoned Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	77,074
Purchased Seasoned Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	8,228
Purchase Credit Deteriorated Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	26,891
Purchase Credit Deteriorated Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	10,722
Purchase Credit Deteriorated Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	8,132
Purchase Credit Deteriorated Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	1,445
Purchase Credit Deteriorated Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	4,754
Purchase Credit Deteriorated Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	1,828
Purchase Credit Deteriorated Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	10
Loan Par Value [Member] \| Purchased Seasoned Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	1,265,358
Loan Par Value [Member] \| Purchased Seasoned Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	733,497
Loan Par Value [Member] \| Purchased Seasoned Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	151,744
Loan Par Value [Member] \| Purchased Seasoned Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	130,492
Loan Par Value [Member] \| Purchased Seasoned Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	164,168
Loan Par Value [Member] \| Purchased Seasoned Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	77,170
Loan Par Value [Member] \| Purchased Seasoned Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	8,287
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	36,180
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	13,074
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	11,291
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	1,845
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	7,867
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	2,086
Loan Par Value [Member] \| Purchase Credit Deteriorated Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	17
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	(12,288)
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(8,103)
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	(817)
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(1,148)
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(2,164)
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	(84)
Discounts from Other Factors Excluding ACL [Member] \| Purchased Seasoned Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	28
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	(5,669)
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(1,497)
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	(1,197)
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(240)
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(2,673)
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	(56)
Discounts from Other Factors Excluding ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	(6)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	(3,293)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(1,108)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	(718)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(114)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(1,254)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	(12)
Credit Marks in ACL [Member] \| Purchased Seasoned Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	(87)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member]
Business Combination [Line Items]
Fair value of acquired loans	(3,620)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Commercial Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(855)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Commercial and Industrial [Member]
Business Combination [Line Items]
Fair value of acquired loans	(1,962)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Residential Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(160)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Agricultural Real Estate [Member]
Business Combination [Line Items]
Fair value of acquired loans	(440)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Agricultural [Member]
Business Combination [Line Items]
Fair value of acquired loans	(202)
Credit Marks in ACL [Member] \| Purchase Credit Deteriorated Loans [Member] \| Consumer [Member]
Business Combination [Line Items]
Fair value of acquired loans	$ (1)