Income Taxes - Schedule of Taxable income and Taxable Net Realized Gains Losses (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions |
12 Months Ended | |||||||||
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Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Income Tax Disclosure [Abstract] | ||||||||||
| Taxable income | $ 318.9 | $ 305.0 | $ 283.0 | |||||||
| Taxable income per share (in dollars per share) | $ 1.80 | $ 1.89 | $ 1.96 | |||||||
| Taxable net realized gains (losses) | $ (6.5) | $ 34.5 | $ (8.2) | |||||||
| Taxable net realized gains (losses) (in dollars per share) | $ (0.04) | $ 0.21 | $ (0.06) | |||||||
| Basic weighted average common shares outstanding (in shares) | 177,392 | 161,082 | 144,091 | 125,189 | 114,742 | 111,985 | 101,132 | 90,929 | 82,519 | 73,753 |
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- Definition Taxable income per share. No definition available.
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- Definition Taxable net income (loss). No definition available.
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- Definition Taxable net realized gain loss. No definition available.
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- Definition Taxable net realized gain (loss) per share. No definition available.
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- References No definition available.
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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