Number Of Lives Served

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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.

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

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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.

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- Definition

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

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No definition available.

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Business Acquisitions Business Acquisition (Assets Liabilities Acquired) (Details) individual_member in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) states	Feb. 28, 2020 individual_member states	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Goodwill	$ 21,687		$ 20,500
Number of States in which Company Operates \| states	50
Beacon Health Options [Member]
Business Acquisition [Line Items]
Number Of Lives Served \| individual_member		34
Number of States in which Company Operates \| states		50
Beacon Health Options [Member] \| Other Segment [Member]
Business Acquisition [Line Items]
Goodwill	$ 1,067
Other intangible assets	$ 752
Minimum [Member] \| Beacon Health Options [Member] \| Other Segment [Member] \| Customer relationships and provider networks
Business Acquisition [Line Items]
Intangible assets amortization period, years	9 years
Maximum [Member] \| Beacon Health Options [Member] \| Other Segment [Member] \| Customer relationships and provider networks
Business Acquisition [Line Items]
Intangible assets amortization period, years	21 years