Segment and Geographic Information - Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment information
Revenue	$ 1,374	$ 1,324	$ 1,342	$ 1,273	$ 1,290	$ 1,263	$ 1,302	$ 1,196	$ 5,313	$ 5,051	$ 4,702
Operating Profit (Loss)	424	$ 410	$ 582	$ 501	(1,148)	$ 366	$ 476	$ 420	1,917	113	1,358
Depreciation & Amortization									157	134	137
Capital Expenditures									139	92	117
Total Assets	8,183				6,773				8,183	6,773
Assets of a business held for sale	503				0				503	0
Intersegment elimination [Member]
Segment information
Revenue									(88)	(86)	(76)
Operating Profit (Loss)									0	0	0
Total operating segments [Member]
Segment information
Revenue									5,313	5,051	4,702
Operating Profit (Loss)									2,055	282	1,617
Depreciation & Amortization									150	124	126
Capital Expenditures									130	84	100
Total Assets	5,812				3,719				5,812	3,719
Unallocated expense [Member]
Segment information
Revenue									0	0	0
Operating Profit (Loss)									(138)	(169)	(259)
Restructuring costs									10	16
Unallocated expense [Member] | Cost Structure Reduction [Member]
Segment information
Restructuring costs											64
Unallocated expense [Member] | Non-Cash Impairment Charge [Member]
Segment information
Restructuring costs											36
Unallocated expense [Member] | Lease Commitments / Terminations [Member]
Segment information
Restructuring costs											13
Corporate [Member]
Segment information
Depreciation & Amortization									7	10	11
Capital Expenditures									9	8	17
Total Assets	1,868				3,054				1,868	3,054
S&P Ratings
Segment information
Revenue									2,428	2,455	2,274
Operating Profit (Loss)									1,078	(583)	882
Depreciation & Amortization									43	43	45
Capital Expenditures									48	33	40
Total Assets	620				624				620	624
S&P Capital IQ and SNL
Segment information
Revenue									1,405	1,237	1,170
Operating Profit (Loss)									228	228	189
Depreciation & Amortization									70	50	49
Capital Expenditures									60	38	39
Total Assets	3,405				1,011				3,405	1,011
S&P DJ Indices
Segment information
Revenue									597	552	493
Operating Profit (Loss)									392	347	266
Depreciation & Amortization									8	7	10
Capital Expenditures									4	2	4
Total Assets	1,181				1,166				1,181	1,166
C&C
Segment information
Revenue									971	893	841
Operating Profit (Loss)									357	290	280
Depreciation & Amortization									29	24	22
Capital Expenditures									18	11	$ 17
Total Assets	$ 606				$ 918				606	$ 918
McGraw Hill Construction [Member]
Segment Reporting Information [Line Items]
Pre-tax gain (loss) on dispositions									$ 11