INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicators (Details) $ in Millions	3 Months Ended
Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 12,592	$ 12,801
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	33
2022	0
2021	309
2020	45
Prior	1,266
Total	$ 1,653	$ 1,709
Weighted Average DSCR	2.30
2024	$ 0
2023	0
2022	0
2021	0
2020	0
Prior	0
Total	$ 0
Commercial mortgage loans \| 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	0.00
Commercial mortgage loans \| 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.58
Commercial mortgage loans \| 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	0.00
Commercial mortgage loans \| 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.92
Commercial mortgage loans \| 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.26
Commercial mortgage loans \| Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.14
Commercial mortgage loans \| Loan to Value Ratio, 0.00% to 59.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	33
2022	0
2021	309
2020	45
Prior	983
Total	$ 1,370
Weighted Average DSCR	2.57
Commercial mortgage loans \| Loan to Value Ratio, 60.00% to 69.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	0
2022	0
2021	0
2020	0
Prior	30
Total	$ 30
Weighted Average DSCR	1.73
Commercial mortgage loans \| Loan to Value Ratio, 70.00% to 79.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	0
2022	0
2021	0
2020	0
Prior	120
Total	$ 120
Weighted Average DSCR	1.26
Commercial mortgage loans \| Loan-to-Value Ratio, 80.00% or greater
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	0
2022	0
2021	0
2020	0
Prior	133
Total	$ 133
Weighted Average DSCR	0.52

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