Name:	ci_PercentageOfBenefitObligationGuaranteesAssociatedWithSoldRetirementBenefitsBusiness
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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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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.

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Indicates, if estimable, the approximate extent to which the proceeds from liquidation of any assets held either as collateral or by third parties would be expected to cover the maximum potential amount of future payments under the guarantee or each group of similar guarantees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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Data Type:	xbrli:monetaryItemType
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

States the reasons why the guarantor is unable to develop an estimate of the maximum potential amount of future payments under its guarantee (or each group of similar guarantees).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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Name:	us-gaap_ProductOrServiceAxis=ci_RetirementAndLifeInsuranceContractsMember
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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Name:	us-gaap_GuaranteeObligationsByNatureAxis=ci_IndemnificationGuaranteeAcquisitionDispositionReinsuranceTransactionsMember
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Data Type:	na
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Name:	us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_MarketValueGuaranteeMember
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