The number of individuals serviced.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-SubTopic 30
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

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Business Acquisitions (Narrative) (Details) individuals in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) states	Feb. 28, 2020 individuals states	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Goodwill	$ 21,691		$ 20,500	$ 20,504
Number of States in which Entity Operates \| states	50
Government Business Segment [Member]
Business Acquisition [Line Items]
Goodwill	$ 8,331		$ 8,279	$ 8,953
Beacon Health Options [Member]
Business Acquisition [Line Items]
Number of lives served \| individuals		34
Number of States in which Entity Operates \| states		50
Beacon Health Options [Member] \| Other Segment [Member]
Business Acquisition [Line Items]
Goodwill	1,072
Other intangible assets	$ 752
Minimum [Member] \| Beacon Health Options [Member] \| Finite-Lived Intangible Assets [Member] \| Other Segment [Member]
Business Acquisition [Line Items]
Intangible assets amortization period, years	9 years
Maximum [Member] \| Beacon Health Options [Member] \| Finite-Lived Intangible Assets [Member] \| Other Segment [Member]
Business Acquisition [Line Items]
Intangible assets amortization period, years	21 years