LOANS AND ALLOWANCE - Past Due Aging of Loan Portfolio by Loan Class (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Loans	$ 12,465,582	$ 12,486,027
Loans > 90 Days or More Past Due And Accruing	2,838	172
Current
Financing Receivable, Past Due [Line Items]
Loans	12,396,707	12,406,783
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	17,406	34,075
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	9,491	11,189
90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	41,978	33,980
Commercial and industrial loans
Financing Receivable, Past Due [Line Items]
Loans	3,722,365	3,670,948
Loans > 90 Days or More Past Due And Accruing	1,585	86
Commercial and industrial loans | Current
Financing Receivable, Past Due [Line Items]
Loans	3,712,412	3,657,447
Commercial and industrial loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	3,279	5,021
Commercial and industrial loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	267	1,622
Commercial and industrial loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	6,407	6,858
Agricultural land, production and other loans to farmers
Financing Receivable, Past Due [Line Items]
Loans	234,431	263,414
Loans > 90 Days or More Past Due And Accruing	0	0
Agricultural land, production and other loans to farmers | Current
Financing Receivable, Past Due [Line Items]
Loans	234,177	263,414
Agricultural land, production and other loans to farmers | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	254	0
Agricultural land, production and other loans to farmers | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Agricultural land, production and other loans to farmers | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Construction
Financing Receivable, Past Due [Line Items]
Loans	941,726	957,545
Loans > 90 Days or More Past Due And Accruing	0	0
Construction | Current
Financing Receivable, Past Due [Line Items]
Loans	941,726	955,588
Construction | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Construction | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	1,957
Construction | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Commercial real estate, non-owner occupied
Financing Receivable, Past Due [Line Items]
Loans	2,368,360	2,400,839
Loans > 90 Days or More Past Due And Accruing	0	0
Commercial real estate, non-owner occupied | Current
Financing Receivable, Past Due [Line Items]
Loans	2,341,845	2,376,184
Commercial real estate, non-owner occupied | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	746	12,995
Commercial real estate, non-owner occupied | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,988	195
Commercial real estate, non-owner occupied | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	22,781	11,465
Commercial real estate, owner occupied
Financing Receivable, Past Due [Line Items]
Loans	1,137,894	1,162,083
Loans > 90 Days or More Past Due And Accruing	0	0
Commercial real estate, owner occupied | Current
Financing Receivable, Past Due [Line Items]
Loans	1,136,405	1,161,869
Commercial real estate, owner occupied | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	939	0
Commercial real estate, owner occupied | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	6	104
Commercial real estate, owner occupied | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	544	110
Residential
Financing Receivable, Past Due [Line Items]
Loans	2,316,490	2,288,921
Loans > 90 Days or More Past Due And Accruing	1,185	0
Residential | Current
Financing Receivable, Past Due [Line Items]
Loans	2,293,704	2,259,496
Residential | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	8,741	11,810
Residential | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	4,197	5,472
Residential | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	9,848	12,143
Home equity
Financing Receivable, Past Due [Line Items]
Loans	618,258	617,571
Loans > 90 Days or More Past Due And Accruing	68	52
Home equity | Current
Financing Receivable, Past Due [Line Items]
Loans	611,309	608,948
Home equity | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,918	3,614
Home equity | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,643	1,647
Home equity | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,388	3,362
Individuals' loans for household and other personal expenditures
Financing Receivable, Past Due [Line Items]
Loans	161,459	168,388
Loans > 90 Days or More Past Due And Accruing	0	0
Individuals' loans for household and other personal expenditures | Current
Financing Receivable, Past Due [Line Items]
Loans	160,530	167,553
Individuals' loans for household and other personal expenditures | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	529	635
Individuals' loans for household and other personal expenditures | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	390	192
Individuals' loans for household and other personal expenditures | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	10	8
Public finance and other commercial loans
Financing Receivable, Past Due [Line Items]
Loans	964,599	956,318
Loans > 90 Days or More Past Due And Accruing	0	34
Public finance and other commercial loans | Current
Financing Receivable, Past Due [Line Items]
Loans	964,599	956,284
Public finance and other commercial loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Public finance and other commercial loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Public finance and other commercial loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	$ 0	$ 34