INSURANCE LIABILITIES - Variable Annuity Contracts with GMDB and GMIB Features (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
GMDB
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 15,472
Separate Accounts	91,323	$ 94,489
Net Amount At Risk By Product And Guarantee, Account Value	106,795
Net Amount at Risk, gross	21,644
Net Amount at Risk, net of amounts reinsured	$ 21,096
Percentage of policyholders over age 70	20.00%
GMDB | Return of Premium
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 15,155
Separate Accounts	48,407
Net Amount At Risk By Product And Guarantee, Account Value	63,562
Net Amount at Risk, gross	125
Net Amount at Risk, net of amounts reinsured	$ 125
Percentage of policyholders over age 70	11.00%
GMDB | Ratchet
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 89
Separate Accounts	8,812
Net Amount At Risk By Product And Guarantee, Account Value	8,901
Net Amount at Risk, gross	94
Net Amount at Risk, net of amounts reinsured	$ 91
Percentage of policyholders over age 70	47.70%
GMDB | Roll-Up
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 57
Separate Accounts	3,021
Net Amount At Risk By Product And Guarantee, Account Value	3,078
Net Amount at Risk, gross	1,864
Net Amount at Risk, net of amounts reinsured	$ 1,319
Percentage of policyholders over age 70	69.80%
GMDB | Combo
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 171
Separate Accounts	31,083
Net Amount At Risk By Product And Guarantee, Account Value	31,254
Net Amount at Risk, gross	19,561
Net Amount at Risk, net of amounts reinsured	$ 19,561
Percentage of policyholders over age 70	53.30%
GMIB
Net Amount at Risk by Product and Guarantee [Line Items]
Separate Accounts	$ 56,341	$ 59,348
Immediate Variable Annuity | GMDB
Net Amount at Risk by Product and Guarantee [Line Items]
Average attained age of policyholders (in years)	55 years 3 months 18 days
Immediate Variable Annuity | GMDB | Minimum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	3.00%
Immediate Variable Annuity | GMDB | Maximum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	6.50%
Immediate Variable Annuity | GMDB | Return of Premium
Net Amount at Risk by Product and Guarantee [Line Items]
Average attained age of policyholders (in years)	51 years 3 months 18 days
Immediate Variable Annuity | GMDB | Ratchet
Net Amount at Risk by Product and Guarantee [Line Items]
Average attained age of policyholders (in years)	68 years 1 month 6 days
Immediate Variable Annuity | GMDB | Roll-Up
Net Amount at Risk by Product and Guarantee [Line Items]
Average attained age of policyholders (in years)	74 years 8 months 12 days
Immediate Variable Annuity | GMDB | Roll-Up | Minimum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	3.00%
Immediate Variable Annuity | GMDB | Roll-Up | Maximum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	6.00%
Immediate Variable Annuity | GMDB | Combo
Net Amount at Risk by Product and Guarantee [Line Items]
Average attained age of policyholders (in years)	70 years
Immediate Variable Annuity | GMDB | Combo | Minimum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	3.00%
Immediate Variable Annuity | GMDB | Combo | Maximum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	6.50%
Immediate Variable Annuity | GMIB
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 237
Separate Accounts	56,341
Net Amount At Risk By Product And Guarantee, Account Value	56,578
Net Amount at Risk, gross	15,561
Net Amount at Risk, net of amounts reinsured	$ 13,415
Average attained age of policyholders (in years)	67 years 9 months 18 days
Weighted average years remaining until annuitization (in years)	2 years 6 months
Immediate Variable Annuity | GMIB | Minimum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	3.00%
Immediate Variable Annuity | GMIB | Maximum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	6.50%
Immediate Variable Annuity | GMIB | Return of Premium
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 0
Separate Accounts	0
Net Amount At Risk By Product And Guarantee, Account Value	0
Net Amount at Risk, gross	0
Net Amount at Risk, net of amounts reinsured	0
Immediate Variable Annuity | GMIB | Ratchet
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	0
Separate Accounts	0
Net Amount At Risk By Product And Guarantee, Account Value	0
Net Amount at Risk, gross	0
Net Amount at Risk, net of amounts reinsured	0
Immediate Variable Annuity | GMIB | Roll-Up
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	17
Separate Accounts	23,124
Net Amount At Risk By Product And Guarantee, Account Value	23,141
Net Amount at Risk, gross	1,100
Net Amount at Risk, net of amounts reinsured	$ 349
Average attained age of policyholders (in years)	64 years
Weighted average years remaining until annuitization (in years)	5 years 8 months 12 days
Immediate Variable Annuity | GMIB | Roll-Up | Minimum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	3.00%
Immediate Variable Annuity | GMIB | Roll-Up | Maximum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	6.00%
Immediate Variable Annuity | GMIB | Combo
Net Amount at Risk by Product and Guarantee [Line Items]
General Account	$ 220
Separate Accounts	33,217
Net Amount At Risk By Product And Guarantee, Account Value	33,437
Net Amount at Risk, gross	14,461
Net Amount at Risk, net of amounts reinsured	$ 13,066
Average attained age of policyholders (in years)	70 years
Weighted average years remaining until annuitization (in years)	8 months 12 days
Immediate Variable Annuity | GMIB | Combo | Minimum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	3.00%
Immediate Variable Annuity | GMIB | Combo | Maximum
Net Amount at Risk by Product and Guarantee [Line Items]
Range of contractually specified interest rates	6.50%