Investments in Other Entities — Equity Method - Equity Method Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity Method Investments [Roll Forward]
Beginning Balance	$ 43,292
Allocation of Income (Loss)	(677)	$ 2,054
Ending Balance	42,615
LaSalle Medical Associates – IPA Line of Business
Equity Method Investments [Roll Forward]
Beginning Balance	13,047
Allocation of Income (Loss)	(718)
Ending Balance	12,329
Pacific Medical Imaging & Oncology Center, Inc.
Equity Method Investments [Roll Forward]
Beginning Balance	1,413
Allocation of Income (Loss)	(14)
Ending Balance	1,399
Diagnostic Medical Group
Equity Method Investments [Roll Forward]
Beginning Balance	2,613
Allocation of Income (Loss)	36
Ending Balance	2,649
531 W. College, LLC – related party
Equity Method Investments [Roll Forward]
Beginning Balance	17,200
Allocation of Income (Loss)	(106)
Ending Balance	17,094
One MSO, LLC - related party
Equity Method Investments [Roll Forward]
Beginning Balance	2,395
Allocation of Income (Loss)	125	$ 125
Ending Balance	2,520
Tag-6 Medical Investment Group, LLC - related party
Equity Method Investments [Roll Forward]
Beginning Balance	4,516
Allocation of Income (Loss)	0
Ending Balance	4,516
Tag-8 Medical Investment Group, LLC - related party
Equity Method Investments [Roll Forward]
Beginning Balance	2,108
Allocation of Income (Loss)	0
Ending Balance	$ 2,108