Schedule II - Condensed Financial Information, Guarantees (Details) - Parent Company [Member] $ in Millions	Dec. 31, 2015 USD ($)
Surety Bond [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Current Carrying Value	$ 77
Guarantee Type, Other, HMO solvency [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	34
Guarantee Type, Other, subsidiary operating as a professional employer organization [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	10
Standby Letter Of Credit, High Deductible Self Insurance Programs Insurer [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	6
Standby Letter Of Credit, Cigna Europe Insurance Company [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	13
Indemnification Guarantee, Cigna Europe Insurance Company Assumed Reinsurance [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	16
Financial Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Current Carrying Value	$ 20

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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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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