v2.3.0.15

Stockholders' Equity (Details) (USD $) Share data in Millions, except Per Share data	9 Months Ended		3 Months Ended	9 Months Ended		9 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 2010 Stock Repurchase Program	Sep. 30, 2011 2010 Stock Repurchase Program	Jan. 31, 2010 2010 Stock Repurchase Program	Sep. 30, 2010 2007 - Share Repurchase Program	Dec. 31, 2007 2007 - Share Repurchase Program	Sep. 30, 2011 Hewitt Associates, Inc (Hewitt)
Common Stock Programs
Share repurchase authorization limit (in dollars)					$ 2,000,000,000		$ 4,600,000,000
Number of shares repurchased			3.8	16.4		2.4
Average price per share of shares purchased under share repurchase program (in dollars per share)			$ 45.61	$ 50.39
Cost of shares repurchased (in dollars)	828,000,000		175,000,000	828,000,000		100,000,000
Cumulative number of shares purchased under share repurchase programs	128.3
Cumulative value of shares purchased under share repurchase programs (in dollars)	5,400,000,000
Additional share repurchase authorization limit (in dollars)			$ 1,200,000,000	$ 1,200,000,000
Number of shares issued for options exercised as part of the Hewitt acquisition								0.5
Number of treasury shares reissued for employee benefit plans	6.7	6.8
Number of treasury shares reissued for employee stock purchase plans	0.2	0.3

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The number of shares of stock issued during the period as a result of any share-based compensation plan as well as a result of employee stock purchase plan.

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Represents the number of treasury shares reissued by the entity for employee benefit plans.

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Represents the number of treasury shares reissued by the entity for employee stock purchase plans.

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Represents the additional amount of funds authorized for share repurchase program by board of directors.

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Represents the maximum amount of funds initially authorized for share repurchase program by board of directors.

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The cumulative number of shares of common stock repurchased to date under repurchase plan.

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The cumulative amount of treasury shares purchased to date under repurchase plan.

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Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 1

-Section B

-Paragraph 7

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Number of shares that have been repurchased during the period and are being held in treasury.

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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Cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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