INVESTMENTS - Fixed Maturities Available-for-sale (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value	$ 4,093	$ 7,553
Less than 12 Months, Gross unrealized Losses	148	351
12 Months or Longer, Fair Value	361	672
12 Months or Longer, Gross unrealized Losses	59	32
Total Fair Value	4,454	8,225
Total Gross unrealized losses	207	383
Corporate
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value	2,574	2,773
Less than 12 Months, Gross unrealized Losses	96	42
12 Months or Longer, Fair Value	277	373
12 Months or Longer, Gross unrealized Losses	53	20
Total Fair Value	2,851	3,146
Total Gross unrealized losses	149	62
U.S. Treasury, government and agency
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value		4,309
Less than 12 Months, Gross unrealized Losses		305
12 Months or Longer, Fair Value		2
12 Months or Longer, Gross unrealized Losses		0
Total Fair Value		4,311
Total Gross unrealized losses		305
States and political subdivisions
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value		112
Less than 12 Months, Gross unrealized Losses		3
12 Months or Longer, Fair Value		0
12 Months or Longer, Gross unrealized Losses		0
Total Fair Value		112
Total Gross unrealized losses		3
Foreign governments
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value	47	11
Less than 12 Months, Gross unrealized Losses	6	0
12 Months or Longer, Fair Value	0	47
12 Months or Longer, Gross unrealized Losses	0	5
Total Fair Value	47	58
Total Gross unrealized losses	6	5
Asset-backed
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value	1,349	319
Less than 12 Months, Gross unrealized Losses	37	1
12 Months or Longer, Fair Value	73	201
12 Months or Longer, Gross unrealized Losses	4	2
Total Fair Value	1,422	520
Total Gross unrealized losses	41	3
Redeemable preferred stock
Available For Sale Securities Continuous Unrealized Loss Position [Line Items]
Less than Twelve Months, Fair Value	123	29
Less than 12 Months, Gross unrealized Losses	9	0
12 Months or Longer, Fair Value	11	49
12 Months or Longer, Gross unrealized Losses	2	5
Total Fair Value	134	78
Total Gross unrealized losses	$ 11	$ 5