INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicator (Detail) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Total Financing Receivable	$ 12,801	$ 13,688
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2023	33
2022	0
2021	310
2020	45
2019	568
Prior	753
Total Financing Receivable	$ 1,709
Weighted average debt-service coverage ratio	2.49
Gross writeoffs, 2023	$ 0
Gross writeoffs, 2022	0
Gross writeoffs, 2021	0
Gross writeoffs, 2020	0
Gross writeoffs, 2019	0
Gross writeoffs, Prior	0
Gross writeoffs, Total	$ 0
Commercial mortgage loans \| 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted average debt-service coverage ratio	2.64
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	3.24
Commercial mortgage loans \| 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted average debt-service coverage ratio	2.05
Commercial mortgage loans \| 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted average debt-service coverage ratio	2.44
Commercial mortgage loans \| Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted average debt-service coverage ratio	2.23
Commercial mortgage loans \| Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 33
2022	0
2021	310
2020	45
2019	422
Prior	599
Total Financing Receivable	$ 1,409
Weighted average debt-service coverage ratio	2.56
Commercial mortgage loans \| Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 0
2022	0
2021	0
2020	0
2019	17
Prior	29
Total Financing Receivable	$ 46
Weighted average debt-service coverage ratio	1.76
Commercial mortgage loans \| Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 0
2022	0
2021	0
2020	0
2019	39
Prior	105
Total Financing Receivable	$ 144
Weighted average debt-service coverage ratio	2.46
Commercial mortgage loans \| Loan to Value Ratio Eighty Percent and Above
Financing Receivable, Credit Quality Indicator [Line Items]
2023	$ 0
2022	0
2021	0
2020	0
2019	90
Prior	20
Total Financing Receivable	$ 110
Weighted average debt-service coverage ratio	1.85

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