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Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Revenue from contracted services and management fees to related parties	$ 6,664,058	$ 6,333,538	$ 6,204,515
Accounts receivable from related parties, current	940,335	941,312
Related Party
Schedule of Equity Method Investments [Line Items]
Revenue from contracted services and management fees to related parties	402,800	374,100	$ 332,000
Accounts receivable from related parties, current	18,200	16,300
Accounts receivable from related parties, noncurrent	4,500	4,300
Liabilities to related parties	$ 66,300	37,000
BIR JV, LLP
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	49.00%
OHRH, LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	49.00%
GlobalRehab—Scottsdale, LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	49.00%
ES Rehabilitation, LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	49.00%
BHSM Rehabilitation, LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	49.00%
RSH Property Ventures, LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	50.00%
Other non current assets
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 316,000	$ 292,600