Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Amortized Cost	$ 15,365.8	$ 16,314.1
Foreign currency, cost	5.0	3.0
Debt financing costs	$ 27.0	$ 34.0
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	$ 11,471.0	$ 12,566.0
Non-controlled/affiliated investments
Amortized Cost	677.0	575.0
Controlled/affiliated investments
Amortized Cost	$ 3,218.0	$ 3,173.0