Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Schedule of Fair Value Liabilities Measured On Recurring Basis Valuation Techniques (Detail)

v3.21.2
Fair Value Measurements - Schedule of Fair Value Liabilities Measured On Recurring Basis Valuation Techniques (Detail) - Contingent Consideration [Member]
$ in Thousands
Sep. 30, 2021
USD ($)
yr
Dec. 31, 2020
USD ($)
yr
Sep. 30, 2020
USD ($)
Dec. 31, 2019
USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Fair Value, Amount | $ $ 8,098 $ 5,572 $ 4,683 $ 3,387
Level 3 [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Fair Value, Amount | $ $ 8,098 $ 5,572    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Expected life of cash flows [Member] | Maximum [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input | yr 6.1 6.8    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Expected life of cash flows [Member] | Minimum [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input | yr 1.7 2.4    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Expected life of cash flows [Member] | Weighted Average [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input | yr 3.7 4.4    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discount rate [Member] | Maximum [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input 3.6 4.3    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discount rate [Member] | Minimum [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input 1.8 2.6    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discount rate [Member] | Weighted Average [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input 2.8 3.4    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Probability of achievement [Member] | Maximum [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input 100.0 100.0    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Probability of achievement [Member] | Minimum [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input 26.9 50.0    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Probability of achievement [Member] | Weighted Average [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Business Combination, Contingent Consideration, Liability, Measurement Input 94.9 86.1    
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discounted cash flow [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Fair Value, Amount | $ $ 8,098 $ 5,572