Income Taxes - Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred income tax assets
Employee pensions and other liabilities	$ 50	$ 59
Other balance sheet reserves and allowances	13	18
Tax loss and credit carryforwards	59	53
Deferred revenue	3	3
Other	2	0
Total deferred income tax assets	127	133
Valuation allowance	(32)	(26)
Net deferred income tax assets	95	107
Deferred income tax liabilities
Intangibles and capitalized software	30	63
Property and equipment	12	22
Other	0	6
Total deferred income tax liabilities	42	91
Total net deferred income tax assets	$ 53	$ 16