Segment and Related Information (Operating Results by Segment) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) Segment	Jun. 30, 2015 USD ($)
Segment Reporting [Abstract]
Number of reportable segments (in segments) \| Segment			4
Segment Reporting Information [Line Items]
Revenue	$ 1,482	$ 1,342	$ 2,823	$ 2,615
Operating Profit	651	582	1,163	1,083
Amortization of intangible assets	23	11	47	23
S&P Global Ratings
Segment Reporting Information [Line Items]
Revenue	682	658	1,234	1,264
Operating Profit	396	361	658	652
Insurance recoveries	37	45	52	80
Legal settlement charge	3	4	6	34
Restructuring charge	6	8	6	8
Amortization of intangible assets	1	1	3	2
S&P Global Market Intelligence
Segment Reporting Information [Line Items]
Revenue	416	324	824	644
Operating Profit	93	63	173	125
Restructuring charge		12		12
Amortization of intangible assets	18	6	36	12
Impairment of intangible asset			24
Disposition-related gain (loss)	(8)		(8)
S&P DJ Indices
Segment Reporting Information [Line Items]
Revenue	153	148	304	291
Operating Profit	100	96	200	191
Amortization of intangible assets	1	1	3	3
S&P Global Platts
Segment Reporting Information [Line Items]
Revenue	255	234	509	459
Operating Profit	93	87	196	173
Restructuring charge		1		1
Amortization of intangible assets	3	3	5	6
Disposition-related gain (loss)	(2)		(4)
Intersegment elimination
Segment Reporting Information [Line Items]
Revenue	(24)	(22)	(48)	(43)
Operating Profit	0	0	0	0
Total operating segments
Segment Reporting Information [Line Items]
Revenue	1,482	1,342	2,823	2,615
Operating Profit	682	607	1,227	1,141
Unallocated expense
Segment Reporting Information [Line Items]
Revenue	0	0	0	0
Operating Profit	(31)	(25)	(64)	(58)
Restructuring charge		1		1
Disposition-related gain (loss)	$ 3		$ 3
McGraw Hill Construction
Segment Reporting Information [Line Items]
Disposition-related gain (loss)				11
McGraw Hill Construction \| Unallocated expense
Segment Reporting Information [Line Items]
Disposition-related gain (loss)		$ 11		$ 11

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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