Revenue and Accounts Receivable - Accounts Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 353,098	$ 339,944
Less: allowance for doubtful accounts	(13,212)	(11,213)
Accounts receivable, net	339,886	328,731
Medicaid
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	128,574	123,647
Managed care
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	82,500	79,722
Medicare
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	61,884	59,797
Private and other payors
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 80,140	$ 76,778