Goodwill, Other Intangibles, and Property and Equipment (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 6,029us-gaap_Goodwill	$ 6,001us-gaap_Goodwill
Impact of foreign currency translation	(43)us-gaap_GoodwillTranslationAdjustments	(8)us-gaap_GoodwillTranslationAdjustments
Goodwill, Ending Balance	5,989us-gaap_Goodwill	6,029us-gaap_Goodwill
Finans Emeklilik [Member]
Goodwill [Line Items]
Goodwill acquired	0	3
Other [Member]
Goodwill [Line Items]
Goodwill acquired	3	33
Global Health Care [Member]
Goodwill [Line Items]
Goodwill, Ending Balance	5,700
Global Supplemental Benefits [Member]
Goodwill [Line Items]
Goodwill, Ending Balance	$ 331

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.

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

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

-Publisher FASB

-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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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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Amount of increase (decrease) from foreign currency translation adjustments 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

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-Section 50

-Paragraph 1

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