SIGNIFICANT ACCOUNTING POLICIES - Policyholders' Account Balances and Future Policy Benefits and Various Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liability For Future Policy Benefits Assumptions [Line Items]
Percentage of life insurance liabilities calculate within traditional life interest rate range	99.40%
Capitalized Computer Software and Hosting Arrangements [Abstract]
Computer software and hosting arrangements	$ 133	$ 130
Amortization of computer software and hosting arrangements	$ 46	$ 47	$ 36
Minimum | Life Insurance Liabilities
Liability For Future Policy Benefits Assumptions [Line Items]
Liability for future policy benefits, interest rate	3.50%
Minimum | Annuity Liabilities
Liability For Future Policy Benefits Assumptions [Line Items]
Liability for policyholder contract deposits, interest rate	1.50%
Maximum | Life Insurance Liabilities
Liability For Future Policy Benefits Assumptions [Line Items]
Liability for future policy benefits, interest rate	6.30%
Maximum | Annuity Liabilities
Liability For Future Policy Benefits Assumptions [Line Items]
Liability for policyholder contract deposits, interest rate	5.40%
Weighted Average | Life Insurance Liabilities
Liability For Future Policy Benefits Assumptions [Line Items]
Liability for future policy benefits, interest rate	5.00%
Weighted Average | Annuity Liabilities
Liability For Future Policy Benefits Assumptions [Line Items]
Liability for policyholder contract deposits, interest rate	3.50%
Computer Software, Intangible Asset | Minimum
Capitalized Computer Software and Hosting Arrangements [Abstract]
Intangible asset useful life	3 years
Computer Software, Intangible Asset | Maximum
Capitalized Computer Software and Hosting Arrangements [Abstract]
Intangible asset useful life	5 years