INVESTMENTS - Middle Market Loans by Key Credit Quality Indicators (Details) - Middle market loans $ in Millions	Mar. 31, 2022 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 141
2021	1,343
2020	892
2019	912
2018	483
Prior	484
Revolving Loans	745
Total Financing Receivable	5,000
BBB Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	117
2020	58
2019	37
2018	23
Prior	0
Revolving Loans	81
Total Financing Receivable	316
BB Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2022	42
2021	337
2020	299
2019	187
2018	111
Prior	59
Revolving Loans	296
Total Financing Receivable	1,331
B Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2022	99
2021	889
2020	513
2019	624
2018	262
Prior	275
Revolving Loans	292
Total Financing Receivable	2,954
CCC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0
2020	22
2019	64
2018	87
Prior	124
Revolving Loans	75
Total Financing Receivable	372
CC Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0
2020	0
2019	0
2018	0
Prior	26
Revolving Loans	1
Total Financing Receivable	27
C and Lower Credit Rating
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0
2020	0
2019	0
2018	0
Prior	0
Revolving Loans	0
Total Financing Receivable	$ 0