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Revenue Recognition - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Revenue from Contract with Customer [Abstract]    
Contract liability revenue recognized $ 7,800,000  
Impairment losses on receivables and contract assets 0 $ 0
Transaction price allocated to uncompleted contracts $ 78,500,000  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]    
Expected time of revenue recognition 18 months