Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Amortized cost	$ 16,182.6	$ 16,314.1
Foreign currency, cost	5.0	3.0
Debt financing costs	$ 34.0	$ 32.0
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	750,000,000	750,000,000
Common stock, shares issued	280,066,433	281,731,750
Common stock, shares outstanding	280,066,433	281,731,750
Non-controlled/unaffiliated investments
Amortized cost	$ 12,395.0	$ 12,566.0
Non-controlled/affiliated investments
Amortized cost	556.0	575.0
Controlled/affiliated investments
Amortized cost	$ 3,232.0	$ 3,173.0

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