Basis of Presentation and Summary of Significant Accounting Policies - Disaggregation of Revenue by Each Payor Type (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 176,058	$ 165,105
Commercial
Disaggregation of Revenue [Line Items]
Revenue	32,266	24,710
Medicare
Disaggregation of Revenue [Line Items]
Revenue	64,677	68,641
Medicaid
Disaggregation of Revenue [Line Items]
Revenue	69,664	62,690
Other third parties
Disaggregation of Revenue [Line Items]
Revenue	$ 9,451	$ 9,064

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details