DERIVATIVE INSTRUMENTS - Offsetting of Financial Assets and Derivative Assets (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	$ 519	$ 555
Gross amount of liabilities offset in balance sheet	0	0
Net amount of derivative assets presented in balance sheet	519	555
Financial instruments, amount not offset	(189)	(174)
Derivative, collateral, obligation to return securities	(103)	(60)
Derivative, collateral, obligation to return cash	(225)	(320)
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement	2	1
Derivative asset, not subject to master netting arrangement	59	62
Derivative asset, fair value, gross asset including not subject to master netting arrangement	578	617
Net amount of derivative assets presented in balance sheet	578	617
Derivative asset, fair value, amount offset against collateral	61	63
Securities lending, gross amounts of recognized financial instruments	4,563	1,788
Securities lending, gross amounts offset in balance sheet	0	0
Securities lending, net amounts of assets presented in balance sheet	4,563	1,788
Securities lending, carrying value of financial instruments not offset in balance sheet	0	0
Securities lending, securities collateral, not offset in balance sheet	0	0
Securities lending, cash collateral, not offset in balance sheet	(4,563)	(1,788)
Securities lending, financial instruments, amount of assets offset against collateral	0	0
Gross amount of recognized assets	5,141	2,405
Gross amounts offset in balance sheet	0	0
Net amounts of assets presented in balance sheet	5,141	2,405
Carrying value of financial instruments not offset in balance sheet	(189)	(174)
Securities collateral, not offset in balance sheet	(103)	(60)
Cash collateral, not offset in balance sheet	(4,788)	(2,108)
Financial instruments, amount of assets offset against collateral	61	63
OTC - Bilateral
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	519	548
Gross amount of liabilities offset in balance sheet	0	0
Net amount of derivative assets presented in balance sheet	519	548
Financial instruments, amount not offset	(189)	(167)
Derivative, collateral, obligation to return securities	(103)	(60)
Derivative, collateral, obligation to return cash	(225)	(320)
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement	2	1
Derivative asset, not subject to master netting arrangement	59	62
OTC- Cleared
Offsetting Assets [Line Items]
Gross amount of recognized derivative assets	0	7
Gross amount of liabilities offset in balance sheet	0	0
Net amount of derivative assets presented in balance sheet	0	7
Financial instruments, amount not offset	0	(7)
Derivative, collateral, obligation to return securities	0	0
Derivative, collateral, obligation to return cash	0	0
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement	$ 0	$ 0