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Reorganization and Business Transformation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Asset write-downs	$ 0	$ 0	$ 0	$ 80
Marketing Applications
Restructuring Cost and Reserve [Line Items]
Employee severance and other employee related cost			2	12
Asset write-downs			1	80
Professional services, legal and other transformation costs			24	27
Total reorganization and business transformation cost			27	119
Other Restructuring \| Marketing Applications
Restructuring Cost and Reserve [Line Items]
Total reorganization and business transformation cost			3
Employee Severance \| Marketing Applications
Restructuring Cost and Reserve [Line Items]
Payments for restructuring			$ 1	$ 18