Basis Of Presentation [Line Items]

No definition available.

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- Definition

Number of members eligible for the health care programs.

+ References

No definition available.

+ Details

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- Definition

Health Plan, Contract Term

+ References

No definition available.

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- Definition

Number of members eligible for the health care programs.

+ References

No definition available.

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- Definition

Number of States For Operated Health Plans

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

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- Details

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Organization and Basis of Presentation (Details) member in Millions, $ in Millions	1 Months Ended		12 Months Ended
	Dec. 31, 2020 USD ($) member state	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) member Segment state	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Basis Of Presentation [Line Items]
Number of reportable segments \| Segment			2
Number of states for operated health plans \| state	15		15
Net cash paid in business combinations			$ 755	$ 0	$ 0
Health Plans
Basis Of Presentation [Line Items]
Number of served members \| member	4.0		4.0
Number of members eligible for the health care programs, approximately \| member	0.2		0.2
Health Plans \| Minimum
Basis Of Presentation [Line Items]
Contract term			3 years
Health Plans \| Maximum
Basis Of Presentation [Line Items]
Contract term			5 years
Magellan Complete Care
Basis Of Presentation [Line Items]
Number of states for operated health plans \| state	18		18
Ownership percentage	100.00%		100.00%
Net cash paid in business combinations	$ 1,037
Affinity Health Plan
Basis Of Presentation [Line Items]
Net cash paid in business combinations		$ 380