Acquisitions and Dispositions (Details 2) (USD $) In Millions, unless otherwise specified				3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Oct. 01, 2010 Hewitt Associates, Inc (Hewitt)	Sep. 30, 2011 Hewitt Associates, Inc (Hewitt) HR Solutions	Sep. 30, 2011 Hewitt Associates, Inc (Hewitt) HR Solutions
Business Acquisition
Value of cash and stock consideration	$ 100	$ 87	$ 4,932
Percentage of aggregate consideration to be paid in cash and in number of shares each			50.00%
Acquisition, integration and financing cost recorded in Other General Expenses				$ 22	$ 42

This element represents acquisition, integration-related costs and financing costs incurred that have been recorded in other general expenses.

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- Definition

This element represents the portion of aggregate merger consideration to be paid in cash and total number of shares of the entity as a condition in the Stock Electing Consideration.

+ Details

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

+ Details

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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.

+ Details

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