INVESTMENTS - Middle Market Loans by Key Credit Quality Indicators (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Total Financing Receivable	$ 13,551	$ 13,688
Middle market loans
Financing Receivable, Credit Quality Indicator [Line Items]
2023	28
2022	652
2021	1,268
2020	790
2019	783
Prior	693
Revolving Loans	870
Total Financing Receivable	5,084
Middle market loans | BBB Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2023	7
2022	75
2021	142
2020	70
2019	37
Prior	17
Revolving Loans	134
Total Financing Receivable	482
Middle market loans | BB Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2023	1
2022	347
2021	444
2020	299
2019	171
Prior	128
Revolving Loans	381
Total Financing Receivable	1,771
Middle market loans | B Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2023	20
2022	230
2021	661
2020	382
2019	464
Prior	406
Revolving Loans	297
Total Financing Receivable	2,460
Middle market loans | CCC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	21
2020	39
2019	111
Prior	128
Revolving Loans	57
Total Financing Receivable	356
Middle market loans | CC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	14
Revolving Loans	1
Total Financing Receivable	15
Middle market loans | C and Lower Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Revolving Loans	0
Total Financing Receivable	$ 0