DERIVATIVES - Derivatives by Category (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Total derivative instruments
Derivatives, Fair Value [Line Items]
Notional Amount	$ 19,045	$ 17,227
Notional Amount - FWH and NI Modco	70,399	66,813
Derivative Assets	12,186	9,189
Derivative Assets - FWH and NI Modco	12,291	10,034
Derivative Liabilities	24,537	18,412
Derivative Liabilities - FWH and NI Modco	2,497	2,204
Net Derivatives	(2,557)	(1,393)
Total embedded derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	8,777	6,729
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	11,669	9,181
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(2,892)	(2,452)
SCS, SIO, MSO and IUL indexed features
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	8,960	7,140
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	11,756	9,081
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(2,796)	(1,941)
Funds withheld payable
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	0	0
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	(87)	100
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	87	(100)
Modco payable
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	(183)	(411)
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	0	0
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(183)	(411)
Derivatives: not designated for hedge accounting
Derivatives, Fair Value [Line Items]
Notional Amount	15,464	13,917
Notional Amount - FWH and NI Modco	70,399	66,813
Derivative Assets	3,310	2,381
Derivative Assets - FWH and NI Modco	12,291	10,034
Derivative Liabilities	12,448	8,830
Derivative Liabilities - FWH and NI Modco	2,497	2,204
Net Derivatives	656	1,381
Derivatives: not designated for hedge accounting | Currency swaps
Derivatives, Fair Value [Line Items]
Notional Amount	803	823
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	3	0
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	4	27
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(1)	(27)
Derivatives: not designated for hedge accounting | Interest swaps
Derivatives, Fair Value [Line Items]
Notional Amount	526	495
Notional Amount - FWH and NI Modco	2,055	2,381
Derivative Assets	1	34
Derivative Assets - FWH and NI Modco	17	83
Derivative Liabilities	4	1
Derivative Liabilities - FWH and NI Modco	16	1
Net Derivatives	(2)	115
Derivatives: not designated for hedge accounting | Futures
Derivatives, Fair Value [Line Items]
Notional Amount	2,349	2,055
Notional Amount - FWH and NI Modco	3,206	3,429
Derivative Assets	0	0
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	0	0
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	0	0
Derivatives: not designated for hedge accounting | Swaps
Derivatives, Fair Value [Line Items]
Notional Amount	840	1,996
Notional Amount - FWH and NI Modco	14,197	12,930
Derivative Assets	3	7
Derivative Assets - FWH and NI Modco	51	45
Derivative Liabilities	0	0
Derivative Liabilities - FWH and NI Modco	17	0
Net Derivatives	37	52
Derivatives: not designated for hedge accounting | Options
Derivatives, Fair Value [Line Items]
Notional Amount	9,311	7,445
Notional Amount - FWH and NI Modco	44,777	41,501
Derivative Assets	3,091	2,169
Derivative Assets - FWH and NI Modco	12,019	9,675
Derivative Liabilities	728	524
Derivative Liabilities - FWH and NI Modco	2,464	2,203
Net Derivatives	11,918	9,117
Derivatives: not designated for hedge accounting | Futures
Derivatives, Fair Value [Line Items]
Notional Amount	1,533	1,000
Notional Amount - FWH and NI Modco	6,164	6,572
Derivative Assets	0	0
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	0	0
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	0	0
Derivatives: not designated for hedge accounting | Credit default swaps
Derivatives, Fair Value [Line Items]
Notional Amount	102	103
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	0	0
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	1	2
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(1)	(2)
Derivatives: not designated for hedge accounting | Margin
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	99	96
Derivative Assets - FWH and NI Modco	204	231
Derivative Liabilities	0	0
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	303	327
Derivatives: not designated for hedge accounting | Collateral
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	113	75
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	11,711	8,276
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(11,598)	(8,201)
Cash flow hedges: | Derivatives: designated for hedge accounting
Derivatives, Fair Value [Line Items]
Notional Amount	3,581	3,310
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	99	79
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	420	401
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	(321)	(322)
Cash flow hedges: | Derivatives: designated for hedge accounting | Currency swaps
Derivatives, Fair Value [Line Items]
Notional Amount	2,629	2,358
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	99	79
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	92	90
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	7	(11)
Cash flow hedges: | Derivatives: designated for hedge accounting | Interest swaps
Derivatives, Fair Value [Line Items]
Notional Amount	952	952
Notional Amount - FWH and NI Modco	0	0
Derivative Assets	0	0
Derivative Assets - FWH and NI Modco	0	0
Derivative Liabilities	328	311
Derivative Liabilities - FWH and NI Modco	0	0
Net Derivatives	$ (328)	$ (311)