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

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

After-tax charges (treated as a special item) related to the liquidation of Penn Treaty Network America Insurance Company, together with its subsidiary American Network Insurance Company (collectively 'Penn Treaty', a long-term care insurance carrier), triggering guaranty fund coverage and accrual of a liability. Special items are excluded from the calculation of 'adjusted income (loss) from operations' because management believes they are not representative of the underlying results of operations. This is generally because the nature and size of these matters are not indicative of our ongoing business operations.

No definition available.

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

No definition available.

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

Sum of before-tax tax amounts classified as special items, attributable to the parent. Special items are excluded from the calculation of 'adjusted income (loss) from operations' because management believes they are not representative of the underlying results of operations. This is generally because the nature and size of these matters are not indicative of our ongoing business operations.

No definition available.

Name:	ci_SpecialItemGainOrLossBeforeTaxAttributableToReportngEntity
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Sum of after-tax amounts classified as special items, attributable to the parent. Special items are excluded from the calculation of 'adjusted income (loss) from operations' because management believes they are not representative of the underlying results of operations. This is generally because the nature and size of these matters are not indicative of our ongoing business operations.

No definition available.

Name:	ci_SpecialItemGainOrLossNetOfTaxAttributableToReportngEntity
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

Name:	ci_SpecialItemsAfterTaxAbstract
Namespace Prefix:	ci_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	ci_SpecialItemsBeforeTaxAbstract
Namespace Prefix:	ci_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Before-tax charges (treated as a special item) related to the liquidation of Penn Treaty Network America Insurance Company, together with its subsidiary American Network Insurance Company (collectively 'Penn Treaty', a long-term care insurance carrier), triggering guaranty fund coverage and accrual of a liability. Special items are excluded from the calculation of 'adjusted income (loss) from operations' because management believes they are not representative of the underlying results of operations. This is generally because the nature and size of these matters are not indicative of our ongoing business operations.

No definition available.

Name:	ci_SpecialItemsChargeBeforeTaxPennTreaty
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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=73531572&loc=d3e1043-128460

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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.

Name:	us-gaap_ExtinguishmentOfDebtGainLossNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629