INVESTMENTS - Debt Securities in HTM in Unrecognized Loss Position (Details) $ in Millions	Dec. 31, 2019 USD ($)
Fair Value
Less than 12 months	$ 13,566
12 months or longer	3,006
Total	16,572
Gross Unrecognized Losses
Less than 12 months	23
12 months or longer	86
Total	109
Unrealized loss, other than temporary impairment, not credit loss, recorded in AOCI	(582)
Mortgage-backed securities
Fair Value
Less than 12 months	3,590
12 months or longer	1,116
Total	4,706
Gross Unrecognized Losses
Less than 12 months	10
12 months or longer	11
Total	21
State and municipal securities
Fair Value
Less than 12 months	34
12 months or longer	1,125
Total	1,159
Gross Unrecognized Losses
Less than 12 months	1
12 months or longer	27
Total	28
Foreign government
Fair Value
Less than 12 months	1,970
12 months or longer	0
Total	1,970
Gross Unrecognized Losses
Less than 12 months	1
12 months or longer	0
Total	1
Asset-backed securities
Fair Value
Less than 12 months	7,972
12 months or longer	765
Total	8,737
Gross Unrecognized Losses
Less than 12 months	11
12 months or longer	48
Total	$ 59