COMMITMENTS, GUARANTEES AND CONTINGENCIES (Details) beneficiary in Millions, $ in Millions		6 Months Ended	12 Months Ended
	Jul. 07, 2020 USD ($)	Jun. 30, 2020 beneficiary State	Dec. 31, 2021	Dec. 31, 2019	Nov. 02, 2017 USD ($)
Loss Contingencies [Line Items]
Percentage of risk score calculated from claims submitted through EDS		50.00%		25.00%
Number of states comprising TRICARE beneficiaries | State		32
Number of TRICARE beneficiaries | beneficiary		6
US Risk Corridor Premium Stabilization Program
Loss Contingencies [Line Items]
Litigation recoveries sought					$ 611
US Risk Corridor Premium Stabilization Program | Subsequent Event
Loss Contingencies [Line Items]
Judgement for Humana	$ 609
Tricare East Region Contract
Loss Contingencies [Line Items]
Contract term years		5 years
Medicare
Loss Contingencies [Line Items]
Percentage of premiums and services revenue		83.00%
Military services
Loss Contingencies [Line Items]
Percentage of premiums and services revenue		1.00%
Medicaid
Loss Contingencies [Line Items]
Percentage of premiums and services revenue		5.00%
Forecast
Loss Contingencies [Line Items]
Percentage of risk score calculated from claims submitted through EDS			75.00%