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Fair Value Measurements - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Fair Value Disclosures [Abstract]    
Transfers from level 1 to level 2 $ 0 $ 0
Transfers from level 2 to level 1 0 0
Transfers in or out of Level 3 $ 0 $ 0