Name:	ci_BelowInvestmentGradeBondWithinOneYear
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Period Type:	instant

No definition available.

Name:	ci_BelowInvestmentGradeMoreThanOneYear
Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
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A bond is considered investment grade if its credit rating is BBB- or higher by Standard & Poor's or Baa3 or higher by Moody's or BBB(low) or higher by DBRS. Generally they are bonds that are judged by the rating agency as likely enough to meet payment obligations that banks are allowed to invest in them.

No definition available.

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

No definition available.

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

- Details

Name:	ci_MoreThanOneYearAbstract
Namespace Prefix:	ci_
Data Type:	xbrli:stringItemType
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Number of issues of below investment grade fixed maturities with a decline in fair value from amortized cost with a length of time of more than one year

No definition available.

Name:	ci_NumberOfIssuesFixedMaturitiesMoreThanOneYearBelowInvestmentGrade
Namespace Prefix:	ci_
Data Type:	xbrli:integerItemType
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Period Type:	instant

Number of issues of investment grade fixed maturities with a decline in fair value from amortized cost with a length of time of more than one year

No definition available.

Name:	ci_NumberOfIssuesFixedMaturitiesMoreThanOneYearInvestmentGrade
Namespace Prefix:	ci_
Data Type:	xbrli:integerItemType
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Number of issues of below investment grade fixed maturities with a decline in fair value from amortized cost with a length of time one year or less

No definition available.

Name:	ci_NumberOfIssuesFixedMaturitiesOneYearOrLessBelowInvestmentGrade
Namespace Prefix:	ci_
Data Type:	xbrli:integerItemType
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Number of issues of investment grade fixed maturities with a decline in fair value from amortized cost with a length of time one year or less

No definition available.