Reconciliation of U.S Federal Income Tax Statutory Rate and Effective Income Tax Rate (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	$ 0	$ 0	$ 1
Changes in valuation allowances	(4.70%)	(0.20%)	(0.60%)
U.S. federal statutory rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal tax benefits	3.80%	2.00%	2.80%
Taxes on foreign operations at rates different than statutory U.S. federal rates	(3.60%)	3.10%	3.70%
Resolution of prior years' examination issues	0.00%	0.00%	(25.60%)
Effective Income Tax Rate Reconciliation, Stock-based Compensation, Percent	(3.40%)	0.00%	0.00%
Non-deductible transaction-related costs	0.00%	0.00%	0.90%
Effective Income Tax Rate Reconciliation, 2017 Tax Reform Act Impact, Percent, Total	(100.80%)	0.00%	0.00%
Other non-deductible expenses	2.20%	1.70%	1.80%
Other	0.40%	0.00%	0.10%
Effective Income Tax Rate, Continuing Operations, Total	(71.10%)	41.60%	18.10%
Other Tax [Member]
Income Tax Disclosure [Line Items]
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	$ 98