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

The after-tax charge against earnings in the period to increase loss contingency liabilities, net of any adjustments to reduce previously estimated charges.

No definition available.

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

Period of time subsequent to execution of the agreement during which the reporting entity will reassess disability claims denied or closed, except for one state.

No definition available.

Name:	ci_ReassessmentPeriod
Namespace Prefix:	ci_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Period of time subsequent to execution of the agreement during which the reporting entity will reassess disability claims denied or closed for California claims.

No definition available.

Name:	ci_ReassessmentPeriodCalifornia
Namespace Prefix:	ci_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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

Amount of loss contingency liability.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Name:	us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of payments made reducing loss contingency liability.

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

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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

Name:	us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_InsuranceRelatedAssessmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: