v3.26.1
INVESTMENT SECURITIES - Investment securities in a continuous unrealized loss position (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value    
Less than 12 months $ 146,192 $ 12,410
12 months or longer 2,708,039 2,760,953
Total 2,854,231 2,773,363
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses    
Less than 12 months 1,477 22
12 months or longer 279,013 273,891
Total 280,490 273,913
Fair Value - Held-To-Maturity    
Less than 12 Months 76,666 31,274
12 Months or Longer 1,083,349 1,095,146
Total 1,160,015 1,126,420
Gross Unrealized Losses - Held-To-Maturity    
Less than 12 Months 800 146
12 Months or Longer 107,642 87,093
Total 108,442 87,239
Unrealized losses in provision for credit losses 0  
Available-for-sale, allowance for credit losses 0  
Government securities    
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value    
Less than 12 months 20,294 0
12 months or longer 2,194,720 2,195,226
Total 2,215,014 2,195,226
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses    
Less than 12 months 114 0
12 months or longer 207,798 204,252
Total 207,912 204,252
Fair Value - Held-To-Maturity    
Less than 12 Months 0 0
12 Months or Longer 1,075,774 1,081,484
Total 1,075,774 1,081,484
Gross Unrealized Losses - Held-To-Maturity    
Less than 12 Months 0 0
12 Months or Longer 107,538 87,003
Total 107,538 87,003
Obligations of state and political subdivisions    
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value    
Less than 12 months 88,426 12,210
12 months or longer 253,871 284,268
Total 342,297 296,478
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses    
Less than 12 months 1,090 22
12 months or longer 26,157 25,905
Total 27,247 25,927
Government agency mortgage-backed securities    
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value    
Less than 12 months 29,213 200
12 months or longer 251,086 272,150
Total 280,299 272,350
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses    
Less than 12 months 241 0
12 months or longer 44,846 43,464
Total 45,087 43,464
Fair Value - Held-To-Maturity    
Less than 12 Months 76,666 31,274
12 Months or Longer 7,575 13,662
Total 84,241 44,936
Gross Unrealized Losses - Held-To-Maturity    
Less than 12 Months 800 146
12 Months or Longer 104 90
Total 904 236
Corporate debt securities    
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value    
Less than 12 months 3,496 0
12 months or longer 4,975 4,912
Total 8,471 4,912
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses    
Less than 12 months 12 0
12 months or longer 25 88
Total 37 88
Government agency collateralized mortgage obligations    
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value    
Less than 12 months 4,763 0
12 months or longer 3,387 4,397
Total 8,150 4,397
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses    
Less than 12 months 20 0
12 months or longer 187 182
Total $ 207 $ 182