Fair Value of Financial Instruments - Summary of Financial Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Recurring - Level 3 - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Level 3 Liabilities	$ 53,158	$ 75,353	$ 98,010	$ 32,971
Business Acquisitions Contingent Consideration, Current
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Level 3 Liabilities	30,152	49,902	36,395	8,614
Business Acquisitions Contingent Consideration, Long-Term
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Level 3 Liabilities	1,000	4,565	$ 9,117	$ 379
Conversion Option
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Level 3 Liabilities	$ 22,006	$ 20,886