Income Taxes - Schedule of Taxable income and Taxable Net Realized Gains Losses (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Income Tax Disclosure [Abstract] | ||||
| Taxable income | $ 88.7 | $ 71.5 | $ 173.8 | $ 144.7 |
| Taxable income, per share (in dollars per share) | $ 0.47 | $ 0.41 | $ 0.94 | $ 0.84 |
| Taxable net realized gains (losses) | $ 22.9 | $ (39.2) | $ 21.0 | $ (35.7) |
| Taxable net realized gains (losses) per share (in dollars per share) | $ 0.12 | $ (0.23) | $ 0.11 | $ (0.21) |
| Weighted average shares outstanding (in shares) | 185,517 | 176,809 | 184,146 | 173,231 |