Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Segment and Geographic Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment information
Revenue	$ 1,290us-gaap_Revenues	$ 1,263us-gaap_Revenues	$ 1,302us-gaap_Revenues	$ 1,196us-gaap_Revenues	$ 1,206us-gaap_Revenues	$ 1,152us-gaap_Revenues	$ 1,205us-gaap_Revenues	$ 1,140us-gaap_Revenues	$ 5,051us-gaap_Revenues	$ 4,702us-gaap_Revenues	$ 4,270us-gaap_Revenues
Operating Profit	(1,148)us-gaap_OperatingIncomeLoss	366us-gaap_OperatingIncomeLoss	476us-gaap_OperatingIncomeLoss	420us-gaap_OperatingIncomeLoss	271us-gaap_OperatingIncomeLoss	395us-gaap_OperatingIncomeLoss	423us-gaap_OperatingIncomeLoss	269us-gaap_OperatingIncomeLoss	113us-gaap_OperatingIncomeLoss	1,358us-gaap_OperatingIncomeLoss	1,170us-gaap_OperatingIncomeLoss
Depreciation & Amortization									134	137	141
Capital Expenditures									92	117	96
Assets held for sale	0				97				0	97
Total Assets	6,771us-gaap_Assets				6,061us-gaap_Assets				6,771us-gaap_Assets	6,061us-gaap_Assets
Intersegment elimination [Member]
Segment information
Revenue									(86)	(76)	(69)
Operating Profit									0	0	0
Total operating segments [Member]
Segment information
Revenue									5,051	4,702	4,270
Operating Profit									282	1,617	1,413
Depreciation & Amortization									124	126	124
Capital Expenditures									84	100	83
Total Assets	3,719				3,751				3,719	3,751
Unallocated expense [Member]
Segment information
Revenue									0	0	0
Operating Profit									(169)	(259)	(243)
Restructuring costs									16
Unallocated expense [Member] \| Cost Structure Reduction [Member]
Segment information
Restructuring costs										64	156
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	52
Corporate [Member]
Segment information
Depreciation & Amortization									10	11	17
Capital Expenditures									8	17	13
Total Assets	3,052				2,213				3,052	2,213
S&P Ratings [Member]
Segment information
Revenue									2,455	2,274	2,034
Operating Profit									(583)	882	809
Depreciation & Amortization									43	45	43
Capital Expenditures									33	40	43
Total Assets	624				630				624	630
S&P Capital IQ [Member]
Segment information
Revenue									1,237	1,170	1,124
Operating Profit									228	189	183
Depreciation & Amortization									50	49	50
Capital Expenditures									38	39	22
Total Assets	1,011				1,054				1,011	1,054
S&P Indices [Member]
Segment information
Revenue									552	493	388
Operating Profit									347	266	202
Depreciation & Amortization									7	10	8
Capital Expenditures									2	4	2
Total Assets	1,166				1,160				1,166	1,160
C&C [Member]
Segment information
Revenue									893	841	793
Operating Profit									290	280	219
Depreciation & Amortization									24	22	23
Capital Expenditures									11	17	16
Total Assets	$ 918				$ 907				$ 918	$ 907