Restructuring (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended		12 Months Ended		3 Months Ended	12 Months Ended							3 Months Ended	9 Months Ended
	Sep. 30, 2013 Restructuring plan 2011	Sep. 30, 2012 Restructuring plan 2011	Dec. 31, 2011 Restructuring plan 2011 Positions	Sep. 30, 2013 Restructuring plan 2011	Sep. 30, 2012 Restructuring plan 2011	Dec. 31, 2012 Restructuring plan 2011		Jun. 30, 2012 Restructuring plan 2011 Employee severance	Dec. 31, 2012 Restructuring plan 2011 S&P Ratings	Dec. 31, 2012 Restructuring plan 2011 S&P Capital IQ	Dec. 31, 2012 Restructuring plan 2011 S&P DJ Indices	Dec. 31, 2012 Restructuring plan 2011 C&C	Dec. 31, 2012 Restructuring plan 2011 Corporate	Dec. 31, 2012 Restructuring plan 2011 Total continuing operations	Dec. 31, 2012 Restructuring plan 2011 MHE	Sep. 30, 2013 Restructuring plan 2012	Sep. 30, 2013 Restructuring plan 2012 Positions	Sep. 30, 2013 Restructuring plan 2012 S&P Ratings	Sep. 30, 2013 Restructuring plan 2012 S&P Capital IQ	Sep. 30, 2013 Restructuring plan 2012 S&P DJ Indices	Sep. 30, 2013 Restructuring plan 2012 C&C	Sep. 30, 2013 Restructuring plan 2012 Corporate	Sep. 30, 2013 Restructuring plan 2012 Total continuing operations	Sep. 30, 2013 Restructuring plan 2012 MHE
Restructuring Cost and Reserve [Line Items]
Workforce reduction (in positions)			250														670
Initial Charge Recorded						$ 66	[1]	$ 5	$ 9	$ 0	$ 0	$ 6	$ 17	$ 32	$ 34		$ 107	$ 15	$ 19	$ 1	$ 12	$ 21	$ 68	$ 39
Ending Reserve Balance						10	[1]		0	0	0	0	4	4	6	29	29	8	6	0	2	4	20	9
Restructuring charges paid	$ 3	$ 6		$ 11	$ 36											$ 17	$ 64

[1] In the second quarter of 2012 we recorded an additional pre-tax restructuring charge of $5 million primarily for employee severance costs as part of the Growth and Value Plan.