Investments - Schedule of Realized and Unrealized Gains and Losses on Investments (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Investments, Debt and Equity Securities [Abstract] | ||||
| Unrealized losses on equity securities held as of the end of the period | $ 2.7 | $ (1.7) | $ 2.0 | $ (3.5) |
| Realized gains for equity securities sold during the period | 0.0 | 0.0 | 0.2 | 0.0 |
| Total (losses) gains recognized in other income, net | $ 2.7 | $ (1.7) | $ 2.2 | $ (3.5) |