DERIVATIVE INSTRUMENTS - Offsetting of Financial Liabilities and Derivative Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	$ 1,205	$ 466
Gross amount of assets offset in balance sheet	0	0
Derivative liability, fair value, amount not offset against collateral	1,205	466
Financial instruments, amounts not offset	(471)	(295)
Derivative, collateral, right to reclaim securities	(662)	(43)
Derivative, collateral, right to reclaim cash	(49)	(69)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement	23	59
Derivative liability, not subject to master netting arrangement	414	231
Derivative liability, fair value, amount offset against collateral, not subject to master netting agreement	414	231
Derivative liability, fair value, gross liability including not subject to master netting arrangement	1,619	697
Net amount of derivative liabilities presented in balance sheet	1,619	697
Derivative liability, fair value, amount offset against collateral	437	290
Gross amounts of recognized financial instruments, offsetting liabilities	3,781	1,661
Gross amounts offset in statement of financial position, offsetting liabilities	0	0
Net amounts of financial instruments presented in balance sheet, offsetting liabilities	3,781	1,661
Carrying value of financial instruments, liabilities not offset in balance sheet	(2,595)	(1,235)
Securities collateral, liabilities not offset in balance sheet	(662)	(43)
Cash collateral, liabilities not offset in balance sheet	(49)	(69)
Financial instruments, amount of liabilities offset against collateral	475	314
Over the Counter - Bilateral
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	1,151	466
Gross amount of assets offset in balance sheet	0	0
Derivative liability, fair value, amount not offset against collateral	1,151	466
Financial instruments, amounts not offset	(471)	(295)
Derivative, collateral, right to reclaim securities	(662)	(43)
Derivative, collateral, right to reclaim cash	(14)	(69)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement	4	59
Derivative liability, not subject to master netting arrangement	414	231
Derivative liability, fair value, amount offset against collateral, not subject to master netting agreement	414	231
Over the Counter - Cleared
Offsetting Liabilities [Line Items]
Gross amount of recognized derivative liabilities	54
Gross amount of assets offset in balance sheet	0
Derivative liability, fair value, amount not offset against collateral	54
Financial instruments, amounts not offset	0
Derivative, collateral, right to reclaim securities	0
Derivative, collateral, right to reclaim cash	(35)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement	19
Securities Lending and Similar Arrangements
Offsetting Liabilities [Line Items]
Gross amounts of recognized financial instruments, offsetting liabilities	2,162	964
Gross amounts offset in statement of financial position, offsetting liabilities	0	0
Net amounts of financial instruments presented in balance sheet, offsetting liabilities	2,162	964
Carrying value of financial instruments, liabilities not offset in balance sheet	(2,124)	(940)
Securities collateral, liabilities not offset in balance sheet	0	0
Cash collateral, liabilities not offset in balance sheet	0	0
Financial instruments, amount of liabilities offset against collateral	$ 38	$ 24