Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Property, plant and equipment, Gross	$ 1,296	$ 1,270
Less accumulated depreciation and amortization	(825)	(780)
Property, plant and equipment, Net	471	490
Land and buildings
Property Plant And Equipment [Line Items]
Property, plant and equipment, Gross	$ 335	337
Land and buildings | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life	25 years
Land and buildings | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life	50 years
Information and communication equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, Gross	$ 858	825
Information and communication equipment | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life	3 years
Information and communication equipment | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life	10 years
Furniture, equipment and other
Property Plant And Equipment [Line Items]
Property, plant and equipment, Gross	$ 103	$ 108
Furniture, equipment and other | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life	3 years
Furniture, equipment and other | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life	10 years