v3.26.1
Share-based Compensation - Weighted Average Assumptions (Details) - Performance Share Units
6 Months Ended
Jun. 30, 2026
$ / shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]  
Risk free interest rate 4.15%
Stock price volatility 56.00%
Contracted term in years 3 years
Expected dividend yield 0.00%
Grant date price of HMH common stock (in dollars per share) $ 18.66