Condensed Consolidated Statements of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenue	$ 1,599,547	$ 1,546,463
Costs and expenses:
Cost of services, exclusive of depreciation and amortization	1,407,010	1,293,449
General and administrative	37,513	35,403
Depreciation and amortization	51,039	49,620
Total costs and expenses	1,495,562	1,378,472
Other operating income	0	34,021
Income from operations	103,985	202,012
Other income and expense:
Equity in earnings of unconsolidated subsidiaries	5,397	9,919
Interest income	0	4,749
Interest expense	(35,514)	(34,402)
Income before income taxes	73,868	182,278
Income tax expense	17,942	45,064
Net income	55,926	137,214
Less: Net income attributable to non-controlling interests	6,809	26,668
Net income attributable to Select Medical Holdings Corporation	$ 49,117	$ 110,546
Earnings per common share (Note 13):
Basic (in dollars per share)	$ 0.37	$ 0.82
Diluted (in dollars per share)	$ 0.37	$ 0.82