BENEFITS PAYABLE - Narrative (Details) claim in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) claim	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Claims Development [Line Items]
Total IBNR | $	$ 5,700
Favorable medical claims reserve development related to prior fiscal years | $	$ 415	$ 825	$ 313
2022 Claims Incurred Year
Claims Development [Line Items]
Cumulative number of reported claims	173.5
2021 Claims Incurred Year
Claims Development [Line Items]
Cumulative number of reported claims	173.3
2020 Claims Incurred Year
Claims Development [Line Items]
Cumulative number of reported claims	149.8