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STOCKHOLDERS' EQUITY (Narrative) (Details) $ / shares in Units, $ in Thousands |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 21, 2024 USD ($) $ / shares shares | Dec. 09, 2022 USD ($) shares | Jun. 09, 2020 $ / shares shares | Dec. 31, 2024 USD ($) item shares | Dec. 31, 2023 USD ($) shares | Dec. 31, 2022 USD ($) shares
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Preferred stock, shares authorized |  |  |  | 500,000 | 500,000 |
Issuance of common stock | $ |  |  |  | $ 228 | $ 778 | $ 3,875
Dilutive effect of stock awards and equity forwards |  |  |  | 1,759,000 | 1,000 | 4,000
Number of active share repurchase programs | item |  |  |  | 0 |  |
Stock repurchase program, number of shares repurchased |  | 1,300,000 |  |  |  |
Stock repurchase program, shares repurchased amount | $ |  | $ 48,200 |  |  |  |
Preferred stock, shares outstanding |  |  |  | 17,250 | 17,250 |
Sandy Spring [Member] | Morgan Stanley & Co. LLC [Member] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Shares issued and sold | 9,859,155 |  |  |  |  |
Underwriter granted option period | 30 days |  |  |  |  |
Proceeds from sale of common stock, settlement period | 18 months |  |  |  |  |
Issuance of common stock | $ | $ 386,400 |  |  |  |  |
Dilutive effect of stock awards and equity forwards |  |  |  | 1,759,194 |  |
Number of stocks option, granted | 1,478,873 |  |  |  |  |
Sandy Spring [Member] | Morgan Stanley & Co. LLC [Member] | Maximum [Member] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Sale of price per share | $ / shares | $ 35.5 |  |  |  |  |
Sandy Spring [Member] | Morgan Stanley & Co. LLC [Member] | Minimum [Member] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Sale of price per share | $ / shares | $ 34.08 |  |  |  |  |
Depositary Shares |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Shares issued and sold |  |  | 6,900,000 |  |  |
Number of shares to be purchased upon the exercise of options |  |  | 900,000 |  |  |
Preferred stock, liquidation preference (usd per share) | $ / shares |  |  | $ 25 |  |  |
Series A Preferred Stock [Member] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [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 |  |  |
Preferred stock, liquidation preference (usd per share) | $ / shares |  |  | $ 10,000 |  |  |

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