SIGNIFICANT ACCOUNTING POLICIES - Effect of Transition Adjustment to Total Equity Resulting (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2023	Apr. 01, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Liability for future policy benefits		$ (15,929)		$ (15,935)
Market risk benefits		(12,995)	$ (8,200)	(15,751)
DAC	$ 4,098	$ 4,771		$ 4,814
Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income
Liability for Future Policy Benefit, Activity [Line Items]
DAC	327
Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income | Accounting Standards Update 2018-12
Liability for Future Policy Benefit, Activity [Line Items]
Liability for future policy benefits	(821)
Market risk benefits	(4,306)
DAC	467
Unearned revenue liability and sales inducement assets	(128)
Total transition adjustment before taxes	(4,788)
Income taxes	1,006
Total transition adjustment (net of taxes)	(3,782)
Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income | Retained Earnings
Liability for Future Policy Benefit, Activity [Line Items]
Liability for future policy benefits	(2)
Market risk benefits	(3,402)
DAC	0
Unearned revenue liability and sales inducement assets	0
Total transition adjustment before taxes	(3,404)
Income taxes	715
Total transition adjustment (net of taxes)	(2,689)
Adjustment for reversal of balances recorded in Accumulated Other Comprehensive Income | Accumulated Other Comprehensive Income
Liability for Future Policy Benefit, Activity [Line Items]
Liability for future policy benefits	(819)
Market risk benefits	(904)
DAC	467
Unearned revenue liability and sales inducement assets	(128)
Total transition adjustment before taxes	(1,384)
Income taxes	291
Total transition adjustment (net of taxes)	$ (1,093)