Commitments And Contingencies [Line Items]

No definition available.

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- Definition

Gross premium tax rate

+ References

No definition available.

+ Details

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- Definition

Merger Agreement, Termination Fee

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Number of states action filed

+ References

No definition available.

+ Details

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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Balance Type:	debit
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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124440162&loc=d3e12021-110248

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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Commitments And Contingencies (Details) $ in Millions	6 Months Ended
Commitments And Contingencies (Details) $ in Millions	Jun. 30, 2021 USD ($) states	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Commitments And Contingencies [Line Items]
Gross premium tax rate, state of California	2.35%
Merger agreement, termination fee		$ 1,850
Long-term purchase commitment, amount	$ 1,166
Minimum [Member]
Commitments And Contingencies [Line Items]
Estimate of possible loss on loss contingencies	0
Maximum [Member]
Commitments And Contingencies [Line Items]
Estimate of possible loss on loss contingencies	$ 250
BCBS Antitrust Litigation [Member]
Commitments And Contingencies [Line Items]
Number of states action filed \| states	28
Estimate of possible loss on loss contingencies	$ 507		$ 594
Anthem, Inc. v. Express Scripts, Inc. [Member]
Commitments And Contingencies [Line Items]
Proceeds originally received at time of divestiture	4,675
Anthem, Inc. v. Express Scripts, Inc. [Member] \| Damages for Pharmacy Pricing [Member]
Commitments And Contingencies [Line Items]
Approximate amount of damages sought for breaches	14,800
Anthem, Inc. v. Express Scripts, Inc. [Member] \| Damages for Operational Breaches [Member]
Commitments And Contingencies [Line Items]
Approximate amount of damages sought for breaches	$ 158