INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicators (Details) $ in Millions	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Total Financing Receivable	$ 13,641	$ 11,960
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2022	211
2021	337
2020	46
2019	599
2018	152
Prior	682
Total Financing Receivable	$ 2,027
Weighted Average Debt Service Coverage Ratio	2.18
Commercial mortgage loans \| 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	0.00
Commercial mortgage loans \| 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.74
Commercial mortgage loans \| 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	1.92
Commercial mortgage loans \| 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.56
Commercial mortgage loans \| 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.06
Commercial mortgage loans \| Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.30
Commercial mortgage loans \| Loan to Value Ratio, 0.00% to 59.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 211
2021	322
2020	46
2019	513
2018	152
Prior	542
Total Financing Receivable	$ 1,786
Weighted Average Debt Service Coverage Ratio	2.23
Commercial mortgage loans \| Loan to Value Ratio, 60.00% to 69.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 0
2021	15
2020	0
2019	46
2018	0
Prior	115
Total Financing Receivable	$ 176
Weighted Average Debt Service Coverage Ratio	2.08
Commercial mortgage loans \| Loan to Value Ratio, 70.00% to 79.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 0
2021	0
2020	0
2019	40
2018	0
Prior	25
Total Financing Receivable	$ 65
Weighted Average Debt Service Coverage Ratio	1.18
Commercial mortgage loans \| Loan-to-Value Ratio, 80.00% or greater
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 0
2021	0
2020	0
2019	0
2018	0
Prior	0
Total Financing Receivable	$ 0
Weighted Average Debt Service Coverage Ratio	0.00

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