Derivative Instruments and Hedging Activities - Effect of Derivative Instruments Designated as Fair Value Hedges and Not Designated as Hedges on Consolidated Statement of Income (Detail) - Cash Flow Hedging - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Derivatives designated as hedges | Cross currency swap | Interest
Derivative Instruments Gain Loss [Line Items]
Gain (Loss) Recognized in Income	$ 18	$ 10
Derivatives not designated as hedges | Foreign exchange contracts | Cost of services/sales
Derivative Instruments Gain Loss [Line Items]
Gain (Loss) Recognized in Income	$ 6	$ (81)