INVESTMENTS - Transitional Real Estate Loans by Key Credit Quality Indicators (Details) - Transitional real estate loans $ in Millions	Dec. 31, 2021 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2021	$ 2,400
2020	353
2019	1,654
2018	829
2017	123
Prior	0
Total Financing Receivable	5,359
Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2021	866
2020	36
2019	502
2018	85
2017	0
Prior	0
Total Financing Receivable	1,489
Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2021	620
2020	136
2019	840
2018	465
2017	50
Prior	0
Total Financing Receivable	2,111
Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2021	846
2020	153
2019	312
2018	279
2017	73
Prior	0
Total Financing Receivable	1,663
Loan to Value Ratio Eighty Percent and Above
Financing Receivable, Credit Quality Indicator [Line Items]
2021	68
2020	28
2019	0
2018	0
2017	0
Prior	0
Total Financing Receivable	$ 96