Segment and Related Information (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) Segment	Jun. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments (in segments) | Segment			4
Revenue	$ 1,342	$ 1,302	$ 2,615	$ 2,498
Operating Profit	582	476	1,083	896
Cash proceeds from sale of business	11		11
S&P Ratings
Segment Reporting Information [Line Items]
Revenue	658	664	1,264	1,233
Operating Profit	361	308	652	548
S&P Capital IQ
Segment Reporting Information [Line Items]
Revenue	324	307	644	608
Operating Profit	63	54	125	107
S&P DJ Indices
Segment Reporting Information [Line Items]
Revenue	148	133	291	269
Operating Profit	96	82	191	174
C&C
Segment Reporting Information [Line Items]
Revenue	234	219	459	431
Operating Profit	87	77	173	146
Intersegment elimination
Segment Reporting Information [Line Items]
Revenue	(22)	(21)	(43)	(43)
Operating Profit	0	0	0	0
Insurance recoveries	45		80
Legal settlement charge	4		34
Total
Segment Reporting Information [Line Items]
Revenue	1,342	1,302	2,615	2,498
Operating Profit	607	521	1,141	975
Unallocated expense
Segment Reporting Information [Line Items]
Revenue	0	0	0	0
Operating Profit	$ (25)	$ (45)	$ (58)	$ (79)