Restructuring (Detail Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended	6 Months Ended	12 Months Ended		6 Months Ended							3 Months Ended		3 Months Ended		12 Months Ended		3 Months Ended
	Dec. 31, 2012 Positions	Dec. 31, 2012 Restructuring Plan, 2012 [Member] Positions	Dec. 31, 2012 Restructuring Plan, 2012 [Member]	Jun. 30, 2012 Restructuring Plan, 2012 [Member]	Dec. 31, 2012 Restructuring Plan, 2012 [Member] Shared Services: Finance & Accounting, Human Resource, Information Technology, and Other Support Services [Member]	Dec. 31, 2012 Restructuring Plan, 2012 [Member] S&P Ratings [Member]	Dec. 31, 2012 Restructuring Plan, 2012 [Member] S&P Capital IQ [Member]	Dec. 31, 2012 Restructuring Plan, 2012 [Member] S&P DJ Indices	Dec. 31, 2012 Restructuring Plan, 2012 [Member] C&C [Member]	Dec. 31, 2012 Restructuring Plan, 2012 [Member] Corporate Segment [Member]	Dec. 31, 2012 Restructuring Plan, 2006 [Member]	Dec. 31, 2011 Restructuring Plan, 2011 [Member]	Dec. 31, 2012 Restructuring Plan, 2011 [Member]	Jun. 30, 2012 Restructuring Plan, 2011 [Member] MHE [Member]	Dec. 31, 2011 Restructuring Plan, 2011 [Member] MHE [Member] Positions	Dec. 31, 2012 Restructuring Plan, 2011 [Member] MHE [Member]	Dec. 31, 2011 Restructuring Plan, 2011 [Member] MHE [Member]	Dec. 31, 2011 Restructuring Plan, 2011 [Member] S&P Ratings [Member]	Dec. 31, 2011 Restructuring Plan, 2011 [Member] C&C [Member]	Dec. 31, 2011 Restructuring Plan, 2011 [Member] Corporate Segment [Member]
Restructuring Cost and Reserve [Line Items]
Percent of headcount eliminated					45.00%
Pre-tax restructuring charge	$ 39	$ 68				$ 15	$ 19	$ 1	$ 12	$ 21		$ 32		$ 5				$ 9	$ 6	$ 17
Workforce reduction, positions	530	670													250
Restructuring charges paid			15													47	4
Restructuring reserve, current		$ 92	$ 92	$ 107							$ 2	$ 66	$ 20