Annual report [Section 13 and 15(d), not S-K Item 405]

SUBSEQUENT EVENTS (Narrative) (Details)

v3.25.0.1
SUBSEQUENT EVENTS (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Jan. 31, 2025
Oct. 21, 2024
Jun. 09, 2020
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Subsequent Event [Line Items]            
Dividends on common stock (in dollars per share)       $ 1.3 $ 1.22 $ 1.16
Dividends on preferred stock (in dollars per share)       687.52 $ 687.52 $ 687.52
Common stock, par value (in dollars per share)       $ 1.33    
Issuance of common stock       $ 228 $ 778 $ 3,875
Sandy Spring [Member] | Morgan Stanley & Co. LLC [Member]            
Subsequent Event [Line Items]            
Shares issued and sold   9,859,155        
Proceeds from sale of common stock, settlement period   18 months        
Issuance of common stock   $ 386,400        
Underwriter granted option period   30 days        
Number of stocks option, granted   1,478,873        
Maximum [Member] | Sandy Spring [Member] | Morgan Stanley & Co. LLC [Member]            
Subsequent Event [Line Items]            
Sale of price per share   $ 35.5        
Minimum [Member] | Sandy Spring [Member] | Morgan Stanley & Co. LLC [Member]            
Subsequent Event [Line Items]            
Sale of price per share   $ 34.08        
Common Class A [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Dividends on common stock (in dollars per share) $ 0.34          
Common Class A [Member] | O 2025 Q1 Preferred Dividends [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Dividends payable, date declared Jan. 31, 2025          
Common Class A [Member] | O 2025 Q1 Common Dividends [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Dividends payable, date to be paid Feb. 28, 2025          
Dividends payable, date of record Feb. 14, 2025          
Depositary Shares            
Subsequent Event [Line Items]            
Shares issued and sold     6,900,000      
Depositary Shares | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Dividends on preferred stock (in dollars per share) $ 0.43          
Series A Preferred Stock [Member]            
Subsequent Event [Line Items]            
Number of preferred stock represented by each depositary share     each representing a 1/400th ownership interest in a share of its Series A preferred stock      
Series A Preferred Stock [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Number of preferred stock represented by each depositary share each representing a 1/400th ownership interest in a share of Series A preferred stock.          
Dividends on preferred stock (in dollars per share) $ 171.88          
Series A Preferred Stock [Member] | O 2025 Q1 Preferred Dividends [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Dividends payable, date to be paid Mar. 03, 2025          
Dividends payable, date of record Feb. 14, 2025