STOCKHOLDERS' DEFICIT - Stock-based compensation (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Stock Based Compensation Expense | ||||
| Stock-based compensation expense | $ 20.7 | $ 6.0 | $ 31.3 | $ 17.7 |
| Total estimated unrecognized compensation cost related to nonvested stock-based compensation arrangements | 33.4 | $ 33.4 | ||
| Weighted average period recognized | 10 months | |||
| Board of director stock award expense | ||||
| Stock Based Compensation Expense | ||||
| Stock-based compensation expense | $ 1.1 | 1.3 | ||
| Special awards expense | ||||
| Stock Based Compensation Expense | ||||
| Stock-based compensation expense | 4.6 | 1.0 | ||
| Restricted stock unit expense | ||||
| Stock Based Compensation Expense | ||||
| Stock-based compensation expense | 11.0 | 3.6 | 13.9 | 9.8 |
| Performance stock unit expense | ||||
| Stock Based Compensation Expense | ||||
| Stock-based compensation expense | $ 9.7 | $ 2.4 | $ 11.7 | $ 5.6 |