Balance Sheet Components - Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Estimated fair value of contingent consideration liability	$ 29,297	$ 4,196
Current operating lease liabilities	10,257	8,992
Accrued variable compensation	21,180	27,030
Deferred revenues	6,187	7,733
Other current liabilities	7,954	5,841
Payroll related costs	5,883	3,716
Professional fees	1,032	1,758
Accrued medical claims expense	2,225	1,905
Accrued subcontractor fees	164	332
Total	$ 84,179	$ 61,503