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STOCKHOLDERS' EQUITY - Treasury Stock (Details) - USD ($) $ in Thousands | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jan. 28, 2021 | Dec. 31, 2020
Treasury Stock |  |  |  |
Aggregate cost of shares repurchased during the period | $ 8,100 | $ 3,162 |  |
Stock Repurchase Program |  |  |  |
Treasury Stock |  |  |  |
Amount of stock repurchases authorized |  |  | $ 50,000 |
Number of shares repurchased during the period | 126,289 |  |  |
Aggregate cost of shares repurchased during the period | $ 8,100 |  |  |
Amount available for repurchase | $ 41,900 |  |  | $ 6,600

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