Financial Highlights - Schedule of Supplemental Ratios (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment Company [Abstract]
Ratio of accrued capital gains incentive fees to average net assets	0.00%	0.00%	0.00%	0.00%	0.00%
Ratio of accrued capital gains incentive fees to average net assets	1.31%	0.83%	0.00%	1.40%	1.16%
Ratio of subordinated income incentive fees to average net assets	4.82%	4.10%	5.36%	4.19%	3.75%
Ratio of interest expense to average net assets	0.25%	0.21%	0.32%	0.17%	0.31%