Revenue - Summary of Total Revenue by Type of Service (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Revenues	$ 191,972	$ 139,370
Screening services
Disaggregation of Revenue [Line Items]
Revenues	189,748	137,209
Other services
Disaggregation of Revenue [Line Items]
Revenues	$ 2,224	$ 2,161

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details