INCOME TAXES - Principal Components of Net Deferred Tax Balances (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Net operating loss carryforward	$ 84	$ 105
Compensation and other accrued expense	218	158
Benefits payable	150	103
Deferred acquisition costs	43	43
Jobs tax credits	0	22
Other	16	16
Unearned revenues	5	7
Investment securities	419	454
Total deferred income tax assets	935	908
Valuation allowance	(73)	(57)
Total deferred income tax assets, net of valuation allowance	862	851
Depreciable property and intangible assets	(642)	(740)
Prepaid expenses	(156)	(132)
Other	(16)	(6)
Total deferred income tax liabilities	(814)	(878)
Total net deferred income tax assets (liabilities)	$ 48
Total net deferred income tax assets (liabilities)		$ (27)