DERIVATIVES AND HEDGING - Offsetting Assets and Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Offsetting of Financial Assets:
Gross Amounts of Recognized Financial Instruments	$ 272	$ 418
Gross Amounts Offset in the Statements of Financial Position	(198)	(333)
Net Amounts Presented in the Statements of Financial Position	74	85
Financial Instruments/Collateral	(74)	(85)
Net Amount	0	0
Derivative instruments
Offsetting of Financial Liabilities:
Gross Amounts of Recognized Financial Instruments	513	826
Gross Amounts Offset in the Statements of Financial Position	(459)	(625)
Net Amounts Presented in the Statements of Financial Position	54	201
Financial Instruments/Collateral	0	0
Net Amount	54	201
Repurchase Agreements
Offsetting of Financial Liabilities:
Gross Amounts of Recognized Financial Instruments	301	311
Gross Amounts Offset in the Statements of Financial Position	0	0
Net Amounts Presented in the Statements of Financial Position	301	311
Financial Instruments/Collateral	(301)	(311)
Net Amount	0	0
Securities Lending Transaction
Offsetting of Financial Liabilities:
Gross Amounts of Recognized Financial Instruments	164	106
Gross Amounts Offset in the Statements of Financial Position	0	0
Net Amounts Presented in the Statements of Financial Position	164	106
Financial Instruments/Collateral	(162)	(103)
Net Amount	2	3
Retained Business
Offsetting of Financial Assets:
Gross Amounts of Recognized Financial Instruments	78	183
Gross Amounts Offset in the Statements of Financial Position	(4)	(98)
Net Amounts Presented in the Statements of Financial Position	74	85
Financial Instruments/Collateral	(74)	(85)
Net Amount	0	0
Retained Business | Derivative instruments
Offsetting of Financial Liabilities:
Gross Amounts of Recognized Financial Instruments	265	353
Gross Amounts Offset in the Statements of Financial Position	(265)	(353)
Net Amounts Presented in the Statements of Financial Position	0	0
Financial Instruments/Collateral	0	0
Net Amount	0	0
Ceded Business
Offsetting of Financial Assets:
Gross Amounts of Recognized Financial Instruments	194	235
Gross Amounts Offset in the Statements of Financial Position	(194)	(235)
Net Amounts Presented in the Statements of Financial Position	0	0
Financial Instruments/Collateral	0	0
Net Amount	0	0
Ceded Business | Derivative instruments
Offsetting of Financial Liabilities:
Gross Amounts of Recognized Financial Instruments	248	473
Gross Amounts Offset in the Statements of Financial Position	(194)	(272)
Net Amounts Presented in the Statements of Financial Position	54	201
Financial Instruments/Collateral	0	0
Net Amount	$ 54	$ 201