BENEFITS PAYABLE - Narrative (Details) claim in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) claim	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Claims Development [Line Items]
Benefits payable including IBNR | $	$ 6,600	$ 7,300
Favorable medical claims reserve development related to prior fiscal years | $	$ 1,000	$ 701	$ 872
2025
Claims Development [Line Items]
Cumulative number of reported claims	229.1
2024
Claims Development [Line Items]
Cumulative number of reported claims	223.7
2023
Claims Development [Line Items]
Cumulative number of reported claims	218.8