COMMITMENTS, GUARANTEES AND CONTINGENCIES (Details) beneficiary in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020 USD ($) beneficiary state
Loss Contingencies [Line Items]
Purchase obligations in 2021		$ 291,000,000
Purchase obligations in 2022		250,000,000
Purchase obligations in 2023		138,000,000
Purchase obligations in 2024		77,000,000
Purchase obligations in 2025		$ 51,000,000
Percentage of risk score calculated from claims submitted through EDS		50.00%
Number of states comprising TRICARE beneficiaries \| state		32
Number of TRICARE beneficiaries \| beneficiary		6,000,000
Forecast
Loss Contingencies [Line Items]
Percentage of risk score calculated from claims submitted through EDS	75.00%
Medicare
Loss Contingencies [Line Items]
Percentage of premiums and services revenue		82.00%
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		6.00%
Tricare East Region Contract
Loss Contingencies [Line Items]
Contract term years		5 years

Contract term, years.

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Number Of States Comprising TRICARE Beneficiaries

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Number Of TRICARE Beneficiaries

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Percentage Of Risk Score Calculated From Claims Submitted Through EDS

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Percentage Of Total Premium And Services Revenues

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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