FINANCIAL HIGHLIGHTS - Schedule of Financial Highlights (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Investment Company, Financial Highlights [Roll Forward]
Net asset value, beginning of period (in dollars per share)	$ 18.96	$ 16.97
Issuances of common stock (in dollars per share)	0.10	0.07
Net investment income for period (in dollars per share)	1.51	1.13
Net realized and unrealized (losses) for period (in dollars per share)	(0.65)	1.56
Net increase in stockholders' equity (in dollars per share)	0.96	2.76
Total distributions to stockholders (in dollars per share)	(1.36)	(1.21)
Net asset value, end of period (in dollars per share)	18.56	18.52
Per share market value at end of period (in dollars per share)	$ 16.88	$ 20.33			$ 21.19			$ 16.89
Total return based on market value	(14.44%)	27.53%
Total return based on net asset value	2.74%	20.87%
Shares outstanding at end of period (in shares)	508,000,000	461,000,000			468,000,000
Ratio/Supplemental Data:
Total stockholders’ equity	$ 9,436	$ 8,537	$ 9,335	$ 9,379	$ 8,868	$ 8,078	$ 7,632	$ 7,176
Ratio of operating expenses to average net assets	9.77%	4.32%
Ratio of net investment income to average net assets	10.73%	3.13%
Portfolio turnover rate	36.00%	54.00%