INCOME TAXES - Schedule of Principal Components of Net Deferred Tax Balances (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Income Tax Disclosure [Abstract]
Benefits payable	$ 174	$ 217
Compensation and other accrued expense	172	171
Net operating loss carryforward	148	93
Deferred acquisition costs	35	39
Other	26	6
Unearned revenues	35	6
Investment securities	544	510
Total deferred income tax assets	1,134	1,042
Valuation allowance	(139)	(85)
Total deferred income tax assets, net of valuation allowance	995	957
Depreciable property and intangible assets	(523)	(502)
Prepaid expenses	(353)	(172)
Other	(35)	(23)
Total deferred income tax liabilities	(911)	(697)
Total net deferred income tax assets (liabilities)	84	260
Amounts recognized in the consolidated balance sheets:
Other long-term assets	$ 84	$ 260