| Income Taxes - Taxable income and Taxable Net Realized Gains Losses (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions | 3 Months Ended | |
|---|---|---|
| Mar. 31, 2024 | Mar. 31, 2023 | |
| Income Tax Disclosure [Abstract] | ||
| Taxable income | $ 78.3 | $ 64.1 | 
| Taxable income, per share (in dollars per share) | $ 0.50 | $ 0.47 | 
| Taxable net realized gains (losses) | $ 5.9 | $ 7.2 | 
| Taxable net realized gains, per share (in dollars per share) | $ 0.04 | $ 0.05 | 
| Basic weighted average common shares outstanding (in shares) | 157,445 | 135,252 | 
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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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