No authoritative reference available.

No definition available.

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- Definition

Expense recognized for health insurance industry assessment fee mandated by the Patient Protection and Affordable Care Act of 2010.

+ References

No definition available.

+ Details

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- Definition

Monetary amount by product segment of present value of future benefits for LTD and workers' compensation to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and unpaid claim costs relating to insurance contracts including estimates of costs relating to incurred but not reported claims based on the estimated ultimate cost of settling the claims (including effects of inflation and other societal and economic factors), using past experience adjusted for current trends and any other factors that would modify past experience.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Percentage discount rate at the high end of a range of reasonable estimates used to calculate present value of an expected stream of future payments for LTD and workers compensation, which is included in the calculation of the amount of the specified guaranteed benefit obligation as of the balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Percentage discount rate at the low end of a range of reasonable estimates used to calculate present value of an expected stream of future payments for LTD and workers compensation, which is included in the calculation of the amount of the specified guaranteed benefit obligation as of the blanace sheet date.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Period after which noncontrolling interests in joint venture may be redeemded by either party to joint venture agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

The percent of the total life insurance in force that is structured as a participating business.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percent of ASO fees reimbursed through performance guarantees

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percent of ASO fees at risk for repayment through performance guarantees

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expense related to deferred policy acquisition costs.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.7(a))

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 7

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 18

-Article 12

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6967983&loc=d3e11264-158415

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 30

-Section 35

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=28247317&loc=d3e10157-158409

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section 45

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6480726&loc=d3e6691-158385

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Balance Type:	debit
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- Definition

The amortization method of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company. The straight-line method is the preferred amortization method, unless another method better reflects the pattern in which the asset is consumed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 35

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=26713198&loc=d3e15372-109273

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

The maximum interest rate applied during the stated period to monetary deposits made by or on behalf of policyholders for contracts that may contractually vary the amount and timing of premium payments without the approval of the insurer and in which premium payments are credited to the policyholder balance, against which amounts are assessed for contract services and to which amounts are credited as income. The policyholder balance provides a base upon which interest accrues to the policyholder and, when compared with the death benefit amount, fixes the insurer's net amount at risk. The insurer can often adjust the schedule of amounts assessed for contract services and the rate at which interest is credited to the policyholder balance.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph b

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.13(b))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

The minimum interest rate applied to deposits made by or on behalf of policyholders to contracts that may contractually vary the amount and timing of premium payments without the approval of the insurer and in which premium payments are credited to the policyholder balance, against which amounts are assessed for contract services and to which amounts are credited as income. The policyholder balance provides a base upon which interest accrues to the policyholder and, when compared with the death benefit amount, fixes the insurer's net amount at risk. The insurer can often adjust the schedule of amounts assessed for contract services and the rate at which interest is credited to the policyholder balance. during the stated period.

+ References

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Period Type:	duration

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Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 09, 2012
Accounting Policies [Abstract]
Health Care Reform Industry Assessment Fee Expense	$ 238,000,000
Allowance for doubtful accounts and unrecoverable reinsurance	105,000,000	47,000,000
Amortization for policy acquisition costs recorded in other operating expense	289,000,000	255,000,000	218,000,000
Statement Line Items [Line Items]
Goodwill	5,989,000,000us-gaap_Goodwill	6,029,000,000us-gaap_Goodwill	6,001,000,000us-gaap_Goodwill
Finite Lived Intangible Assets Amortization Method	accelerated or straight-line basis
Future policy benefits interest rate assumptions range low	0.10%
Future policy benefits interest rate assumptions range high	10.00%
Discount rate assumption for LTD and Workers' comp claim liabilities range low	4.10%
Discount rate assumption for LTD and Workers' comp claim liabilities range high	5.50%
Discounted liability for long-term disability and workers' compensation business	3,900,000,000	3,500,000,000
Business Acquisition [Line Items]
Percent of ASO fees reimbursed for performance guarantees	1.00%ci_PerformanceGuaranteePercentPayment
Percent of Administrative Service Only fees at risk for performance guarantees	12.00%ci_PerformanceGuaranteePercentRisk
Percent of total life insurance in force that is participating business	1.00%
Finans Emeklilik [Member]
Business Acquisition [Line Items]
Ownership Percentage Retained by Noncontrolling Owners				49.00%
Minority Interest Redemption Term				15 years
Global Health Care [Member]
Statement Line Items [Line Items]
Goodwill	5,700,000,000
Global Supplemental Benefits [Member]
Statement Line Items [Line Items]
Goodwill	$ 331,000,000
Minimum [Member]
Statement Line Items [Line Items]
Finite Lived Intangible Assets Useful Life	3 years
Maximum [Member]
Statement Line Items [Line Items]
Finite Lived Intangible Assets Useful Life	30 years
Building And Building Improvements Member \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	10 years
Building And Building Improvements Member \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	40 years
Internal-use software [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	1 year
Internal-use software [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	5 years
Internally developed software \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	3 years
Internally developed software \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	7 years
Furniture and equipment (including computer equipment) \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	3 years
Furniture and equipment (including computer equipment) \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property Plant And Equipment Useful Life	10 years