Condensed Consolidated Statements of Changes in Net Assets - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Investment Company, Net Assets [Roll Forward]
Beginning balance		$ 5,394,573	$ 4,350,271	$ 4,952,041	$ 4,158,966
Issuance of common shares, net of offering and underwriting costs		310,268	210,246	662,401	335,515
Reinvestment of dividends	[1]	5,074	4,635	15,981	15,206
Net investment income		185,903	160,791	524,849	481,454
Net realized gain (loss)		(15,109)	(10,536)	(6,964)	4,488
Net change in unrealized appreciation (depreciation)		(19,130)	20,740	13,720	(31,299)
Dividends declared and payable from net investment income		(160,912)	(133,552)	(461,361)	(361,735)
Ending balance		5,700,667	4,602,595	5,700,667	4,602,595
Par Amount
Investment Company, Net Assets [Roll Forward]
Beginning balance		198	165	186	160
Issuance of common shares, net of offering and underwriting costs		11	8	23	11
Reinvestment of dividends	[1]				2
Ending balance		209	173	209	173
Additional Paid in Capital
Investment Company, Net Assets [Roll Forward]
Beginning balance		5,064,855	4,168,948	4,701,827	4,033,113
Issuance of common shares, net of offering and underwriting costs		310,257	210,238	662,378	335,504
Reinvestment of dividends	[1]	5,074	4,635	15,981	15,204
Ending balance		5,380,186	4,383,821	5,380,186	4,383,821
Distributable Earnings (Loss)
Investment Company, Net Assets [Roll Forward]
Beginning balance		329,520	181,158	250,028	125,693
Net investment income		185,903	160,791	524,849	481,454
Net realized gain (loss)		(15,109)	(10,536)	(6,964)	4,488
Net change in unrealized appreciation (depreciation)		(19,130)	20,740	13,720	(31,299)
Dividends declared and payable from net investment income		(160,912)	(133,552)	(461,361)	(361,735)
Ending balance		$ 320,272	$ 218,601	$ 320,272	$ 218,601

[1] The par amount of the shares is less than 1,000 and rounds to zero.