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FAIR VALUE DISCLOSURES - Additional Information (Detail) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Fair Value, Option, Quantitative Disclosures [Line Items]      
Equity method investments at fair value $ 6,307 $ 8,421  
Level 3      
Fair Value, Option, Quantitative Disclosures [Line Items]      
Equity method investments at fair value $ 6,307 $ 8,421 $ 0