Segment Information - Selected Financial Data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment information
Revenue	$ 6,664,058	$ 6,333,538	$ 6,204,515
Adjusted EBITDA	807,425	646,863	947,359
Total assets	7,689,631	7,665,293	7,360,171
Capital expenditures	229,200	190,372	180,537
Corporate, non-Segment
Segment information
Revenue	357,705	333,002	292,001
Adjusted EBITDA	(133,667)	(98,712)	(33,229)
Total assets	248,204	327,214	238,258
Capital expenditures	6,126	9,762	18,756
Critical Illness Recovery Hospital | Operating Segments
Segment information
Revenue	2,299,773	2,234,132	2,246,772
Adjusted EBITDA	246,015	111,344	267,993
Total assets	2,496,886	2,484,542	2,304,116
Capital expenditures	93,036	79,524	65,690
Rehabilitation Hospital | Operating Segments
Segment information
Revenue	979,585	916,763	849,340
Adjusted EBITDA	221,875	198,034	184,704
Total assets	1,233,888	1,200,767	1,194,136
Capital expenditures	21,922	14,426	13,003
Outpatient Rehabilitation | Operating Segments
Segment information
Revenue	1,188,914	1,125,282	1,084,361
Adjusted EBITDA	111,868	101,860	138,275
Total assets	1,380,447	1,371,123	1,348,316
Capital expenditures	38,776	40,677	36,301
Concentra | Operating Segments
Segment information
Revenue	1,838,081	1,724,359	1,732,041
Adjusted EBITDA	361,334	334,337	389,616
Total assets	2,330,206	2,281,647	2,275,345
Capital expenditures	$ 69,340	$ 45,983	$ 46,787