INVESTMENTS - Net Unrealized Investment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 11,565	$ 12,359
Ending balance	11,643	11,565
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | Net Unrealized Gains (Losses) on Investments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	3,084	(577)
Net investment gains (losses) arising during the period	5,953	3,872
Included in Net income (loss)	(802)	(211)
Excluded from net income (loss)	0	0
Impact of net unrealized investment gains (losses)	0	0
Net unrealized investment gains (losses) excluding OTTI losses	8,235	3,084
Net unrealized investment gains (losses) with OTTI losses	(5)	0
Ending balance	8,230	3,084
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | DAC
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(826)	37
Impact of net unrealized investment gains (losses)	360	(863)
Net unrealized investment gains (losses) excluding OTTI losses	(466)	(826)
Ending balance	(466)	(826)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | Policyholders’ Liabilities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(192)	(69)
Impact of net unrealized investment gains (losses)	(1,623)	(123)
Net unrealized investment gains (losses) excluding OTTI losses	(1,815)	(192)
Ending balance	(1,814)	(192)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | Deferred Income Tax Asset (Liability)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(433)	125
Impact of net unrealized investment gains (losses)	(818)	(558)
Net unrealized investment gains (losses) excluding OTTI losses	(1,251)	(433)
Ending balance	(1,250)	(433)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | AOCI Gain (Loss) Related to Net Unrealized Investment Gains (Losses)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	1,633	(484)
Net investment gains (losses) arising during the period	5,953	3,872
Included in Net income (loss)	(802)	(211)
Excluded from net income (loss)	0	0
Impact of net unrealized investment gains (losses)	(2,081)	(1,544)
Net unrealized investment gains (losses) excluding OTTI losses	4,703	1,633
Net unrealized investment gains (losses) with OTTI losses	(3)	0
Ending balance	4,700	1,633
Fixed Maturities | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | DAC
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Net unrealized investment gains (losses) with OTTI losses	0	0
Fixed Maturities | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | Policyholders’ Liabilities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Net unrealized investment gains (losses) with OTTI losses	1	0
Fixed Maturities | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent | Unrealized Investment Gains Losses All Other | Deferred Income Tax Asset (Liability)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Net unrealized investment gains (losses) with OTTI losses	$ 1	$ 0