Segment and Other Supplemental Information - Regional Segment Revenue and Gross Margin for Company (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information
Segment revenue	$ 513	$ 599	$ 1,004	$ 1,144
Segment gross profit	265	332	516	626
Stock-based compensation costs	(3)	(4)	(7)	(8)
Amortization of acquisition-related intangible assets costs	0	0	0	(2)
Acquisition, integration, reorganization and transformation-related costs	(2)	(2)	(4)	(5)
Amortization of capitalized software costs	(18)	(16)	(39)	(32)
Selling, general and administrative expenses	165	172	320	346
Research and development expenses	78	51	148	108
Impairment of goodwill, acquired intangibles and other assets	0	0	0	80
(Loss) income from operations	(1)	87	(2)	45
Americas Data and Analytics
Segment Reporting Information
Segment revenue	271	325	538	620
Segment gross profit	158	194	309	369
International Data and Analytics
Segment Reporting Information
Segment revenue	242	239	466	455
Segment gross profit	107	121	207	223
Total Data and Analytics
Segment Reporting Information
Segment revenue	513	564	1,004	1,075
Segment gross profit	265	315	516	592
Marketing Applications
Segment Reporting Information
Segment revenue	0	35	0	69
Segment gross profit	$ 0	$ 17	0	34
Impairment of goodwill, acquired intangibles and other assets			$ 6	$ 80

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Amortization of Intangible Assets, Due to Acquisition

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of expense for amortization of capitalized computer software costs.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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