Financial Highlights (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investment Company, Net Assets [Roll Forward]
Net asset value, beginning of period (in usd per share)	$ 14.99	$ 15.08	$ 14.74	$ 15.24	$ 15.10	$ 15.03	$ 14.85	$ 0
Net investment income (in usd per share)	1.93	1.41	1.25	1.33	1.54	1.68	1.40	0.42
Net realized and unrealized gain (loss) (in usd per share)	0.10	(0.22)	0.33	(0.35)	0.08	(0.19)	0.13	0.36
Total from operations (in usd per share)	2.03	1.19	1.58	0.98	1.62	1.49	1.53	0.78
Repurchase of common shares (in usd per share)	0.02	0.01	0	0.08	(0.03)	0	0	14.13
Distributions declared from earnings (in usd per share)	(1.59)	(1.29)	(1.24)	(1.56)	(1.45)	(1.42)	(1.35)	(0.06)
Total increase (decrease) in net assets (in usd per share)	0.46	(0.09)	0.34	(0.50)	0.14	0.07	0.18	14.85
Net asset value, end of period (in usd per share)	$ 15.45	$ 14.99	$ 15.08	$ 14.74	$ 15.24	$ 15.10	$ 15.03	$ 14.85
Shares outstanding, end of period (in shares)	389,732,868	392,476,687	393,766,855	389,966,688	392,129,619	216,204,837	97,959,595	45,833,313
Per share market value at end of period (in usd per share)	$ 14.76	$ 11.55	$ 14.16	$ 12.66	$ 17.89
Total Return, based on market value	43.30%	(9.90%)	21.70%	(20.10%)	22.00%
Total Return, based on net asset value	15.60%	9.00%	11.30%	8.70%	10.70%	10.20%	10.60%	(0.60%)
Ratio of total expenses to average net assets	13.90%	11.00%	9.10%	5.00%	4.40%	6.40%	6.30%	6.50%
Ratio of net investment income to average net assets	12.70%	9.50%	8.40%	9.10%	10.00%	10.90%	9.00%	2.90%
Net assets, end of period	$ 6,021,393	$ 5,882,403	$ 5,937,877	$ 5,746,434	$ 5,977,283	$ 3,264,845	$ 1,472,579	$ 680,525
Weighted-average shares outstanding (in shares)	390,104,585	394,006,852	392,297,907	388,645,561	324,630,279	146,422,371	67,082,905	21,345,191
Total capital commitments, end of period						$ 5,471,160	$ 5,067,680	$ 2,313,237
Ratio of total contributed capital to total committed capital, end of period						57.40%	27.90%	28.80%
Portfolio turnover rate	13.20%	11.60%	43.10%	14.70%	17.70%	29.10%	30.80%	25.40%
Total expenses to average net assets				7.30%	5.90%	6.40%	6.30%