Schedule II - Condensed Financial Information, Guarantees (Details) $ in Millions	Dec. 31, 2016 USD ($)
Market Value Guarantee [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	$ 42
Current Carrying Value	5
Expiring In 2017 [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	10
Expiring In 2022 [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	25
Expiring in 2026 [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	7
Parent Company [Member] \| Surety Bond [Member]
Guarantee Obligations [Line Items]
Current Carrying Value	98
Parent Company [Member] \| Guarantee Type, Other, HMO solvency [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	34
Parent Company [Member] \| Guarantee Type, Other, subsidiary operating as a professional employer organization [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	10
Parent Company [Member] \| Standby Letter Of Credit, High Deductible Self Insurance Programs Insurer [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	6
Parent Company [Member] \| Standby Letter Of Credit, Cigna Europe Insurance Company [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	8
Parent Company [Member] \| Indemnification Guarantee, Cigna Europe Insurance Company Assumed Reinsurance [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	14
Parent Company [Member] \| Financial Guarantee [Member]
Guarantee Obligations [Line Items]
Current Carrying Value	31
Parent Company [Member] \| Market Value Guarantee [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	42
Parent Company [Member] \| Expiring In 2017 [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	10
Parent Company [Member] \| Expiring In 2022 [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	25
Parent Company [Member] \| Expiring in 2026 [Member]
Guarantee Obligations [Line Items]
Maximum Exposure, Undiscounted	$ 7

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

+ Details

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Balance Type:	credit
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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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- Details

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- Details

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- Details

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