Name:	ci_AcquirerMergerAgreementTerminationFee
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Stock consideration per share of acquirer to company shareholders under the proposed merger agreement.

No definition available.

Name:	ci_AcquirerStockConsideratoinPerShareToCompanyStockholdersUnderMergerAgreement
Namespace Prefix:	ci_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

Merger agreement termination fee due from acquirer to the Company if regulatory approval is not attained or if closing does not occur by January 31, 2017 (subject to extension to April 30, 2017 under certain circumstances).

No definition available.

Name:	ci_AcquirorMergerAgreementTerminationFeeRegulatoryApprovalNotAttained
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Merger agreement termination fee due from acquirer to Company if acquirer shareholders vote down the proposed merger.

No definition available.

Name:	ci_AcquirorMergerAgreementTerminationFeeShareholderRejection
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This element represents after-tax acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

No definition available.

Name:	ci_BusinessCombinationAcquisitionRelatedCostsAfterTax
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Cash consideration per share to company stockholders under the proposed merger agreement.

No definition available.

Name:	ci_CashConsiderationPerShareToCompanyStockholdersUnderMergerAgreement
Namespace Prefix:	ci_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

Merger agreement termination fee due from the Company to the Acquirer upon certain circumstances if the merger does not occur.

No definition available.

Name:	ci_CompanyMergerAgreementTerminationFee
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Merger agreement termination fee due from Company to acquirer if Company shareholders vote down the proposed merger.

No definition available.

Name:	ci_CompanyMergerAgreementTerminationFeeShareholderRejection
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Closing price of Anthem, Inc. common stock

No definition available.

Name:	ci_SharePriceAnthem
Namespace Prefix:	ci_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

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.

No definition available.

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460