Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Amount attributable to The McGraw-Hill Companies, Inc. common shareholders:
Income from continuing operations	$ 153	$ 158
Income (loss) from discontinued operations	582	(35)
Net income	$ 735	$ 123
Basic weighted-average number of common shares outstanding	280.5	278.0
Effect of stock options and other dilutive securities	3.8	5.8
Diluted weighted-average number of common shares outstanding	284.3	283.8
Basic EPS:
Income from continuing operations (in usd per share)	$ 0.55	$ 0.57
Loss from discontinued operations, net of tax (in usd per share)	$ 2.07	$ (0.13)
Net income (in usd per share)	$ 2.62	$ 0.44
Diluted EPS:
Income from continuing operations (in usd per share)	$ 0.54	$ 0.56
Loss from discontinued operations, net of tax (in usd per share)	$ 2.05	$ (0.13)
Net income (in usd per share)	$ 2.59	$ 0.43
Restricted Stock [Member]
Common Shares Outstanding (Textual) [Abstract]
Outstanding shares not included in the computation of diluted earnings per share for both restricted stock and stock options	1.4	1.6
Stock Options [Member]
Common Shares Outstanding (Textual) [Abstract]
Outstanding shares not included in the computation of diluted earnings per share for both restricted stock and stock options	3.0	4.2