Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.20.4
Summary of Significant Accounting Policies - Additional Information (Detail)
12 Months Ended
Dec. 31, 2020
USD ($)
Segment
Dec. 31, 2019
USD ($)
Dec. 31, 2018
Jan. 01, 2019
USD ($)
Significant Accounting Policies [Line Items]        
Number of reportable segments | Segment 1      
Number of operating segments | Segment 1      
Operating lease assets $ 12,303,000 $ 14,007,000   $ 14,300,000
Operating lease liabilities 14,771,000     $ 15,300,000
Lease obligation $ 10,300,000      
Cash and cash equivalents maturity period 90 days      
Investment maturity period 90 days      
Impairment of long-lived assets $ 0      
Expected dividend yield 0.00% 0.00% 0.00%  
Defined contribution plan, plan name 401(k)      
Defined contribution plan, matching contribution percentage   50.00%    
Defined contribution plan, maximum percentage of an individual's eligible earnings   6.00%    
Defined contribution plan contributions by employer $ 2,100,000 $ 1,600,000    
Minimum        
Significant Accounting Policies [Line Items]        
Property, plant and equipment, useful life 3 years      
Maximum        
Significant Accounting Policies [Line Items]        
Property, plant and equipment, useful life 5 years      
ASU 2016-02        
Significant Accounting Policies [Line Items]        
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] true      
Change in Accounting Principle, Accounting Standards Update, Adoption Date Jan. 01, 2019      
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] true      
ASU 2016-13        
Significant Accounting Policies [Line Items]        
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] true      
Change in Accounting Principle, Accounting Standards Update, Adoption Date Jan. 01, 2020      
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] true      
ASU 2018-15        
Significant Accounting Policies [Line Items]        
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] true      
Change in Accounting Principle, Accounting Standards Update, Adoption Date Jan. 01, 2020      
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] true      
ASU 2019-12        
Significant Accounting Policies [Line Items]        
Change in Accounting Principle, Accounting Standards Update, Adoption Date Jan. 01, 2020      
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] true      
Change in Accounting Principle, Accounting Standards Update, Early Adoption [true false] true