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CASH EQUIVALENTS AND MARKETABLE SECURITIES - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]          
Realized losses of available-for-sale securities $ 0 $ 0 $ 0 $ 0  
Other-than-temporarily impaired investments     $ 0   $ 0