Goodwill and Other Intangible Assets (Details) $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Changes in the net carrying amount of goodwill by operating segment (in millions)
Beginning balance	$ 8,860
Goodwill related to current year acquisitions	18
Goodwill related to disposals	(13)
Goodwill related to prior year acquisitions	4
Foreign currency translation	(298)
Ending balance	8,571
Risk Solutions [Member]
Changes in the net carrying amount of goodwill by operating segment (in millions)
Beginning balance	5,911
Goodwill related to current year acquisitions	3
Goodwill related to disposals	0
Goodwill related to prior year acquisitions	4
Foreign currency translation	(266)
Ending balance	5,652
HR Solutions [Member]
Changes in the net carrying amount of goodwill by operating segment (in millions)
Beginning balance	2,949
Goodwill related to current year acquisitions	15
Goodwill related to disposals	(13)
Goodwill related to prior year acquisitions	0
Foreign currency translation	(32)
Ending balance	$ 2,919

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

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-SubTopic 20

-Section 50

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