INVESTMENTS - Middle Market Loans by Key Credit Quality Indicators (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 11,828	$ 12,801
Middle market loans
Financing Receivable, Credit Quality Indicator [Line Items]
2024	376
2023	131
2022	710
2021	1,142
2020	706
Prior	1,291
Revolving Loans	155
Total	4,511	$ 4,677
2024	0
2023	0
2022	0
2021	27
2020	0
Prior	23
Revolving Loans	0
Total	50
Middle market loans | BBB Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2024	10
2023	27
2022	39
2021	80
2020	93
Prior	80
Revolving Loans	16
Total	345
Middle market loans | BB Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2024	206
2023	55
2022	396
2021	421
2020	276
Prior	409
Revolving Loans	72
Total	1,835
Middle market loans | B Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2024	156
2023	49
2022	253
2021	557
2020	249
Prior	598
Revolving Loans	49
Total	1,911
Middle market loans | CCC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	22
2021	78
2020	88
Prior	113
Revolving Loans	17
Total	318
Middle market loans | CC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2024	4
2023	0
2022	0
2021	0
2020	0
Prior	23
Revolving Loans	1
Total	28
Middle market loans | C and Lower Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
2021	6
2020	0
Prior	68
Revolving Loans	0
Total	$ 74