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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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

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-SubTopic 20

-Section 50

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Amount of assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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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.

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Acquisitions and Dispositions - Acquisitions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 business	Mar. 31, 2013 business	Dec. 31, 2013
Intangible assets:
Goodwill	$ 9,030		$ 8,997
Business Acquisition 1 [Member]
Business Acquisition
Consideration	5	2
Intangible assets:
Goodwill	4	2
Other intangible assets	4	1
Total	8	3
Risk Solutions [Member]
Business Acquisition
Number of business acquired under business combination	1
Intangible assets:
Goodwill	6,052		6,020
HR Solutions [Member]
Business Acquisition
Number of business acquired under business combination	1	1
Intangible assets:
Goodwill	$ 2,978		$ 2,977