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Fair Value Measurements - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Transfers within the hierarchy $ 0 $ 0
Nonrecurring [Member] | Level 3 [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Impairment charge of right-of-use and leasehold improvement assets $ 5,800,000