Condensed Consolidated Statements of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net operating revenues	$ 1,393,343	$ 1,267,401	$ 4,079,338	$ 3,816,575
Costs and expenses:
Cost of services, exclusive of depreciation and amortization	1,183,111	1,087,062	3,465,353	3,247,606
General and administrative	34,385	29,975	94,401	90,951
Depreciation and amortization	52,941	50,527	160,072	149,022
Total costs and expenses	1,270,437	1,167,564	3,719,826	3,487,579
Income from operations	122,906	99,837	359,512	328,996
Other income and expense:
Loss on early retirement of debt	(18,643)	0	(18,643)	(10,255)
Equity in earnings of unconsolidated subsidiaries	6,950	5,432	18,710	14,914
Gain on sale of businesses (Note 5)	0	2,139	6,532	9,016
Interest expense	(54,336)	(50,669)	(156,611)	(147,991)
Income (loss) before income taxes	56,877	56,739	209,500	194,680
Income tax expense	12,847	14,060	52,140	47,460
Net income	44,030	42,679	157,360	147,220
Less: Net income attributable to non-controlling interests	13,298	9,762	40,978	34,053
Net income attributable to Select Medical Holdings Corporation	$ 30,732	$ 32,917	$ 116,382	$ 113,167
Earnings per common share (Note 12):
Basic (in dollars per share)	$ 0.23	$ 0.24	$ 0.86	$ 0.84
Diluted (in dollars per share)	$ 0.23	$ 0.24	$ 0.86	$ 0.84