Balance Sheet Components - Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Accrued variable compensation	$ 8,377	$ 27,030
Current operating lease liabilities	9,538	8,992
Deferred revenues	8,521	7,733
Estimated fair value of contingent consideration liability	10,228	4,196
Other current liabilities	6,462	5,841
Payroll related costs	3,031	3,716
Accrued medical claims expense	1,568	1,905
Professional fees	1,815	1,758
Accrued subcontractor fees	324	332
Total	$ 49,864	$ 61,503