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Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Summary of Loans [Abstract]
Loans	$ 9,969,910	$ 9,650,713
Deferred loan origination (fees) costs, net	(64,700)	(98,200)
Loans held for sale	9,744	3,371
Loans serviced for unrelated third parties	982,500	856,900
Mortgage servicing rights	900	1,000
Loans and Leases Receivable, Related Parties [Roll Forward]
Balance at January 1	1,087	2,516
New loans	412	705
Repayments	(501)	(2,134)
Balance at December 31	998	1,087
Commercial and Industrial [Member]
Summary of Loans [Abstract]
Loans	1,426,482	1,354,248
Commercial Real Estate [Member]
Summary of Loans [Abstract]
Loans	3,876,698	3,626,910
Residential Real Estate [Member]
Summary of Loans [Abstract]
Loans	2,142,249	2,125,804
Loans held for sale	2,400	400
Home Equity [Member]
Summary of Loans [Abstract]
Loans	334,268	337,214
Indirect Auto [Member]
Summary of Loans [Abstract]
Loans	1,273,253	1,130,132
Residential Solar [Member]
Summary of Loans [Abstract]
Loans	820,079	917,755
Loans held for sale	7,300	2,900
Other Consumer [Member]
Summary of Loans [Abstract]
Loans	96,881	158,650
Agricultural and Agricultural Real Estate Mortgages [Member]
Summary of Loans [Abstract]
Loans serviced for unrelated third parties	$ 24,700	$ 26,400

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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