v3.25.2
GOODWILL AND INTANGIBLE ASSETS (Narrative) (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2025
USD ($)
Jun. 30, 2024
USD ($)
Jun. 30, 2025
USD ($)
segment
Jun. 30, 2024
USD ($)
Apr. 01, 2025
USD ($)
Dec. 31, 2024
USD ($)
Apr. 01, 2024
USD ($)
Finite-Lived Intangible Assets [Line Items]              
Number of operating segments | segment     2        
Goodwill $ 1,710,912,000   $ 1,710,912,000     $ 1,214,053,000  
Intangible Assets 351,381,000   351,381,000     84,563,000  
Impairment of goodwill or intangible assets     0        
Intangible assets, amortization expense $ 18,433,000 $ 5,995,000 $ 23,832,000 $ 7,889,000      
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) 5 months   5 months        
Other Intangible Assets [Member] | Maximum [Member]              
Finite-Lived Intangible Assets [Line Items]              
Intangible assets, amortization period (years) 16 years   16 years        
American National              
Finite-Lived Intangible Assets [Line Items]              
Goodwill           $ 288,842,000 $ 288,842,000
American National | Wholesale Banking              
Finite-Lived Intangible Assets [Line Items]              
Goodwill             210,800,000
American National | Consumer Banking              
Finite-Lived Intangible Assets [Line Items]              
Goodwill             $ 78,000,000
Sandy Spring              
Finite-Lived Intangible Assets [Line Items]              
Goodwill $ 496,859,000   $ 496,859,000   $ 496,859,000    
Sandy Spring | Wholesale Banking              
Finite-Lived Intangible Assets [Line Items]              
Goodwill         387,600,000    
Sandy Spring | Consumer Banking              
Finite-Lived Intangible Assets [Line Items]              
Goodwill         $ 109,300,000