DERIVATIVES - Offsetting of Financial Assets and Liabilities and Derivative Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Total derivatives
Assets
Gross Amount Recognized	$ 6,573	$ 5,804
Gross Amount Offset in the Balance Sheets	6,134	5,429
Net Amount Presented in the Balance Sheets	439	375
Gross Amount not Offset in the Balance Sheets	(118)	(77)
Net Amount	321	298
Liabilities
Gross Amount Recognized	6,203	5,474
Gross Amount Offset in the Balance Sheets	6,134	5,429
Net Amount Presented in the Balance Sheets	69	45
Gross Amount not Offset in the Balance Sheets	0	0
Net Amount	69	45
Other financial instruments
Assets
Gross Amount Recognized	1,523	1,781
Gross Amount Offset in the Balance Sheets	0	0
Net Amount Presented in the Balance Sheets	1,523	1,781
Gross Amount not Offset in the Balance Sheets	0	0
Net Amount	1,523	1,781
Other invested assets
Assets
Gross Amount Recognized	8,096	7,585
Gross Amount Offset in the Balance Sheets	6,134	5,429
Net Amount Presented in the Balance Sheets	1,962	2,156
Gross Amount not Offset in the Balance Sheets	(118)	(77)
Net Amount	1,844	2,079
Other financial liabilities
Liabilities
Gross Amount Recognized	1,462	1,723
Gross Amount Offset in the Balance Sheets	0	0
Net Amount Presented in the Balance Sheets	1,462	1,723
Gross Amount not Offset in the Balance Sheets	0	0
Net Amount	1,462	1,723
Other liabilities
Liabilities
Gross Amount Recognized	7,665	7,197
Gross Amount Offset in the Balance Sheets	6,134	5,429
Net Amount Presented in the Balance Sheets	1,531	1,768
Gross Amount not Offset in the Balance Sheets	0	0
Net Amount	$ 1,531	$ 1,768