Variable Interest Entities (VIEs) (Details) - USD ($) $ in Thousands		Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents		$ 237,942	$ 233,097		$ 193,470
Investments in marketable securities		42,893	53,417
Receivables, net		55,280	10,608
Receivables, net – related party		76,410	69,376
Other receivables		13,260	9,647
Prepaid expenses and other current assets		14,631	18,637
Total current assets		444,416	398,782
Non-current assets
Intangible assets, net		80,148	82,807
Goodwill		252,379	253,039
Investments in other entities – equity method		44,383	41,715
Operating lease right-of-use assets		14,770	15,441
Other assets		4,424	5,928
Total non-current assets		467,915	453,581
Total assets	[1]	912,331	852,363
Current liabilities
Accounts payable and accrued expenses		48,252	43,951
Fiduciary accounts payable		6,305	10,534
Medical liabilities		95,758	55,783	$ 51,479	$ 50,330
Dividends payable		556	556
Current portion of long-term debt		1,503	780
Finance lease liabilities		543	486
Operating lease liabilities		2,625	2,629
Total current liabilities		160,436	115,371
Non-current liabilities
Long-term debt, net of current portion and deferred financing costs		183,101	182,917
Deferred tax liability		9,686	9,127
Finance lease liabilities, net of current portion		1,172	973
Operating lease liabilities, net of current portion		12,558	13,198
Other long-term liabilities		13,706	14,777
Total non-current liabilities		220,223	220,992
Total liabilities	[1]	380,659	336,363
Variable Interest Entity, Primary Beneficiary
Current assets
Cash and cash equivalents		142,862	161,762
Investments in marketable securities		38,534	49,066
Receivables, net		23,539	7,251
Receivables, net – related party		69,948	62,180
Income taxes receivable		0	1,342
Other receivables		1,885	1,833
Prepaid expenses and other current assets		7,649	11,734
Loan receivable – related party		4,000	4,000
Amount due from affiliate		25,150	6,598
Total current assets		313,567	305,766
Non-current assets
Land, property, and equipment, net		68,598	49,547
Intangible assets, net		61,301	58,282
Goodwill		116,226	109,656
Loans receivable – related party		69	89
Investment in affiliates		529,569	802,821
Investments in other entities – equity method		44,383	41,715
Investment in privately held entities		405	405
Operating lease right-of-use assets		4,644	4,953
Other assets		1,849	3,219
Total non-current assets		827,044	1,070,687
Total assets		1,140,611	1,376,453
Current liabilities
Accounts payable and accrued expenses		14,700	11,591
Fiduciary accounts payable		6,305	10,534
Medical liabilities		61,220	44,000
Income taxes payable		481	0
Dividends payable		556	556
Current portion of long-term debt		1,503	780
Finance lease liabilities		543	110
Operating lease liabilities		1,249	1,250
Total current liabilities		86,557	68,821
Non-current liabilities
Long-term debt, net of current portion and deferred financing costs		7,063	7,114
Deferred tax liability		3,978	1,982
Finance lease liabilities, net of current portion		1,172	193
Operating lease liabilities, net of current portion		3,651	3,950
Other long-term liabilities		8,542	9,614
Total non-current liabilities		24,406	22,853
Total liabilities		$ 110,963	$ 91,674

[1] The Company’s consolidated balance sheets include the assets and liabilities of its consolidated VIEs. The consolidated balance sheets include total assets that can be used only to settle obligations of the Company’s consolidated VIEs totaling $585.9 million and $567.0 million as of March 31, 2022 and December 31, 2021, respectively, and total liabilities of the Company’s consolidated VIEs for which creditors do not have recourse to the general credit of the primary beneficiary of $111.0 million and $91.7 million as of March 31, 2022 and December 31, 2021, respectively. The VIE balances do not include $529.6 million of investment in affiliates and $25.2 million of amounts due from affiliates as of March 31, 2022 and $802.8 million of investment in affiliates and $6.6 million of amounts due to affiliates as of December 31, 2021 as these are eliminated upon consolidation and not presented within the consolidated balance sheets. See Note 16 – Variable Interest Entities (VIEs) for further detail.