Organization (Details) $ / shares in Units, $ in Thousands				9 Months Ended
	Jul. 26, 2024 USD ($) $ / shares shares	Jun. 25, 2024	Mar. 04, 2024	Sep. 30, 2024 USD ($) clinic state health_center $ / shares	Sep. 30, 2023 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of occupational health centers operated by entity | health_center				549
Number of onsite health clinics | clinic				156
Number of states in which entity operates | state				42
Member interests converted to common shares			1
Stock split conversion ratio		0.233
Common stock, par value (in dollars per share) | $ / shares				$ 0.01
Proceeds from Initial Public Offering				$ 511,198	$ 0
Select Medical Corporation | Concentra Group Holdings Parent
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Outstanding member interest				81.74%
IPO
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of shares issued in initial public offering (in shares) | shares	22,500,000
Common stock, par value (in dollars per share) | $ / shares	$ 0.01
Sale of stock, price per share (in dollars per share) | $ / shares	$ 23.50
Proceeds from Initial Public Offering	$ 499,700
Underwriting discounts and commissions	29,100
Net proceeds of IPO and debt financing transactions, excluding amounts repaid for debt	34,700
IPO | Select Medical Revolving Promissory Note
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Repayments of debt	$ 420,000
Over-Allotment Option
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of shares issued in initial public offering (in shares) | shares	750,000
Consideration received on transaction	$ 16,700
Payments of stock issuance costs	$ 1,000