Reconciliation of U.S Federal Income Tax Statutory Rate and Effective Income Tax Rate (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Line Items]
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	$ 3	$ 0	$ 0
Changes in valuation allowances	6.30%	(4.70%)	(0.20%)
U.S. federal statutory rate	21.00%	35.00%	35.00%
State and local income taxes, net of federal tax benefits	5.50%	3.80%	2.00%
Taxes on foreign operations at rates different than statutory U.S. federal rates	(5.20%)	(3.60%)	3.10%
Effective Income Tax Rate Reconciliation, Stock-based Compensation, Percent	(0.80%)	(3.40%)	0.00%
Effective Income Tax Rate Reconciliation, 2017 Tax Reform Act Impact, Percent, Total	11.20%	(100.80%)	0.00%
Other non-deductible expenses	1.10%	2.20%	1.70%
Other	(0.90%)	0.40%	0.00%
Effective Income Tax Rate, Continuing Operations, Total	38.20%	(71.10%)	41.60%