Quarterly report pursuant to Section 13 or 15(d)

GOODWILL AND INTANGIBLE ASSETS (Narrative) (Details)

v3.24.3
GOODWILL AND INTANGIBLE ASSETS (Narrative) (Details)
 3 Months Ended 9 Months Ended
Sep. 30, 2024
USD ($)
Sep. 30, 2023
USD ($)
Sep. 30, 2024
USD ($)
segment
Sep. 30, 2023
USD ($)
Apr. 01, 2024
USD ($)
Dec. 31, 2023
USD ($)
Finite-Lived Intangible Assets [Line Items]            
Number of operating segments | segment     2      
Goodwill $ 1,212,710,000   $ 1,212,710,000     $ 925,211,000
Intangible Assets 90,176,000   90,176,000     19,183,000
Impairment of goodwill or intangible assets     0      
Intangible assets, amortization expense 5,804,000 $ 2,193,000 13,693,000 $ 6,687,000    
Wholesale Banking            
Finite-Lived Intangible Assets [Line Items]            
Goodwill 845,239,000   845,239,000     639,180,000
Intangible Assets 9,032,000   9,032,000     1,302,000
Consumer Banking            
Finite-Lived Intangible Assets [Line Items]            
Goodwill 362,245,000   362,245,000     286,031,000
Intangible Assets 830,000   830,000     989,000
Corporate Other            
Finite-Lived Intangible Assets [Line Items]            
Goodwill 5,226,000   5,226,000     0
Intangible Assets $ 80,314,000   $ 80,314,000     16,892,000
Core Deposits [Member] | Minimum [Member]            
Finite-Lived Intangible Assets [Line Items]            
Intangible assets, amortization period (years) 4 years   4 years      
Core Deposits [Member] | Maximum [Member]            
Finite-Lived Intangible Assets [Line Items]            
Intangible assets, amortization period (years) 10 years   10 years      
Other Intangible Assets [Member] | Minimum [Member]            
Finite-Lived Intangible Assets [Line Items]            
Intangible assets, amortization period (years) 4 years   4 years      
Other Intangible Assets [Member] | Maximum [Member]            
Finite-Lived Intangible Assets [Line Items]            
Intangible assets, amortization period (years) 10 years   10 years      
American National            
Finite-Lived Intangible Assets [Line Items]            
Goodwill $ 287,499,000   $ 287,499,000   $ 287,499,000 $ 0
Increase in goodwill 5,200,000          
American National | Wholesale Banking            
Finite-Lived Intangible Assets [Line Items]            
Goodwill 209,900,000   209,900,000   209,900,000  
Intangible Assets 8,400,000   8,400,000      
American National | Consumer Banking            
Finite-Lived Intangible Assets [Line Items]            
Goodwill 77,600,000   77,600,000   $ 77,600,000  
American National | Corporate Other            
Finite-Lived Intangible Assets [Line Items]            
Intangible Assets $ 76,300,000   $ 76,300,000