INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicators (Details) $ in Millions	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 13,133	$ 13,688
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2023	19
2022	0
2021	311
2020	45
2019	584
Prior	775
Total	$ 1,734
Weighted Average DSCR	2.43
Commercial mortgage loans \| 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.08
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	3.18
Commercial mortgage loans \| 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.05
Commercial mortgage loans \| 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average DSCR	2.44
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]
2023	$ 19
2022	0
2021	311
2020	45
2019	459
Prior	596
Total	$ 1,430
Weighted Average DSCR	2.57
Commercial mortgage loans \| Loan to Value Ratio, 60.00% to 69.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 0
2022	0
2021	0
2020	0
2019	17
Prior	87
Total	$ 104
Weighted Average DSCR	1.82
Commercial mortgage loans \| Loan to Value Ratio, 70.00% to 79.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 0
2022	0
2021	0
2020	0
2019	80
Prior	44
Total	$ 124
Weighted Average DSCR	1.49
Commercial mortgage loans \| Loan-to-Value Ratio, 80.00% or greater
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 0
2022	0
2021	0
2020	0
2019	28
Prior	48
Total	$ 76
Weighted Average DSCR	2.20

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