Earnings Per Share (Details) (USD $)
In Millions, except Per Share data | 3 Months Ended | 9 Months Ended |
|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 |
|---|
| Amounts attributable to The McGraw-Hill Companies, Inc. common shareholders: | | | | |
| Income from continuing operations | $ 366.7 | $ 379.2 | $ 698.3 | $ 673.3 |
| Loss from discontinued operations, net of tax | (1.1) | 0.7 | (1.7) | 0.9 |
| Net income attributable to the Company | $ 365.6 | $ 379.9 | $ 696.6 | $ 674.2 |
| Basic weighted-average number of common shares outstanding | 297.8 | 307.2 | 302.2 | 310.6 |
| Effect of stock options and other dilutive securities | 5.8 | 2.1 | 5.2 | 2.3 |
| Diluted weighted-average number of common shares outstanding | 303.6 | 309.3 | 307.4 | 312.9 |
| Basic EPS: | | | | |
| Income from continuing operations | $ 1.23 | $ 1.23 | $ 2.31 | $ 2.17 |
| Loss from discontinued operations, net of tax | $ 0 | $ 0.01 | $ 0 | $ 0 |
| Net income | $ 1.23 | $ 1.24 | $ 2.31 | $ 2.17 |
| Diluted EPS: | | | | |
| Income from continuing operations | $ 1.21 | $ 1.23 | $ 2.27 | $ 2.15 |
| Loss from discontinued operations, net of tax | $ 0 | $ 0 | $ 0 | $ 0 |
| Net income | $ 1.21 | $ 1.23 | $ 2.27 | $ 2.15 |
Restricted Stock [Member] | | | | |
| Common Shares Outstanding (Textuals) [Abstract] | | | | |
| Outstanding shares not included in the computation of diluted earnings per share for both restricted stock and stock options | | | 1.6 | 3.2 |
Stock Options [Member] | | | | |
| Common Shares Outstanding (Textuals) [Abstract] | | | | |
| Outstanding shares not included in the computation of diluted earnings per share for both restricted stock and stock options | 9.9 | 24.4 | 10.2 | 23.9 |