Stock Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Stock based Compensation
Number of shares authorized (in shares)	5,925,000
Number of shares authorized, remaining (in shares)	4,446,532
Class C Restricted Interests
Stock based Compensation
Award vesting period	5 years
Fair value of vested shares		$ 0.7	$ 0.7
Stock compensation expense		$ 0.1	$ 0.7
Class C Restricted Options
Stock based Compensation
Exercise of stock options, weighted average exercise price (in dollars per share)		$ 1.18	$ 1.18
Restricted stock awards
Stock based Compensation
Award vesting period	4 years
Stock compensation expense	$ 0.9
Restricted stock awards | Select Medical Corporation
Stock based Compensation
Stock compensation expense	$ 1.5	$ 0.5
Employee Stock Option
Stock based Compensation
Award vesting period	5 years
Award expiration term	10 years
Class C Options
Stock based Compensation
Stock compensation expense		$ 0.1	$ 1.5
Exercise of stock options, weighted average exercise price (in dollars per share)		$ 2.66	$ 2.66
Total intrinsic value of options exercised		$ 6.3	$ 5.9
Stock options granted during period (in shares)	0	0	0
Class B Options
Stock based Compensation
Stock options granted during period (in shares)	0	0	0