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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- Definition 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 -Subparagraph b + Details
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