Revenue Recognition - Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenues	$ 194,133	$ 152,316
United States
Disaggregation of Revenue [Line Items]
Total revenues	187,217	144,957
Americas, excluding U.S.
Disaggregation of Revenue [Line Items]
Total revenues	741	813
Europe, Middle East, India, Africa
Disaggregation of Revenue [Line Items]
Total revenues	3,691	4,459
Asia Pacific and Other
Disaggregation of Revenue [Line Items]
Total revenues	2,484	2,087
Insurance carriers
Disaggregation of Revenue [Line Items]
Total revenues	164,742	100,399
Laboratory partners
Disaggregation of Revenue [Line Items]
Total revenues	20,737	44,535
Patients
Disaggregation of Revenue [Line Items]
Total revenues	8,654	7,382
Licensing and other
Disaggregation of Revenue [Line Items]
Total revenues	$ 4,131	$ 31,932