Name:	ci_AdjustedIncomeLossFromOperations
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- References

No definition available.

Name:	ci_AfterTaxAdjustmentsToReconcileToAdjustedIncomeFromOperationsAbstract
Namespace Prefix:	ci_
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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

No definition available.

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

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
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Period Type:	duration

Amount after taxes of the net realized gains or (losses) on investments during the period.

No definition available.

Name:	ci_RealizedInvestmentGainsLossesNetOfTaxes
Namespace Prefix:	ci_
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After-tax charges associated with litigation matters that are classified as special items, attributable to the parent. Special items reflect amounts that management does not believe are representative of underlying results of operations.

No definition available.

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

Sum of net of tax amounts classified as special items, attributable to the parent. Special items reflect amounts that management does not believe are representative of underlying results of operations.

No definition available.

Name:	ci_SpecialItemGainOrLossNetOfTaxAttributableToReportingEntity
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- References

No definition available.

Name:	ci_SpecialItemsAbstract
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The difference between the reacquisition price and the net carrying amount of the extinguished debt recognized currently as a component of income in the period of extinguishment, net of tax.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6401765&loc=d3e13305-112630

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Name:	us-gaap_ExtinguishmentOfDebtGainLossNetOfTax
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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1377-109256

Name:	us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
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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.

Name:	us-gaap_SegmentReportingInformationLineItems
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Period Type:	duration

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