SIGNIFICANT ACCOUNTING POLICIES - Assumption Updates and Model Changes (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in Accounting Estimate [Line Items]
Income (loss) from operations, before income taxes			$ (18)	$ (38)	$ (58)
Net income (loss)			(13)	(9)	(45)
Policy charges and fee income			275	261	245
Policyholders’ benefits			239	184	107
Amortization of deferred policy acquisition costs, net			25	31	92
Assumptions Updates
Change in Accounting Estimate [Line Items]
Income (loss) from operations, before income taxes	$ 21	$ 2	(12)	(16)	(17)
Net income (loss)	$ 17	$ 2	(9)	(13)	(14)
Policy charges and fee income			2	(9)	14
Policyholders’ benefits			10	(1)	(8)
Amortization of deferred policy acquisition costs, net			$ 4	$ 8	$ 39
5-year Historical Average Over A 10-year Period
Change in Accounting Estimate [Line Items]
Interest rate assumptions				2.25%