Income Taxes (Reconciliation of Statutory U.S. Corporate Federal Income Tax Rate to Effective Income Tax Rate) (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	35.00%	35.00%	35.00%
Changes in rate due to:
U.S. tax cost - Tax Cuts & Jobs Act	11.00%	0.00%	0.00%
U.S./foreign tax differential	(9.30%)	(17.70%)	(8.20%)
U.S. current tax benefit on foreign exchange realization	(4.90%)	(3.00%)	0.00%
U.S. state and local taxes	(2.30%)	(3.70%)	(1.90%)
U.S. tax (benefit) cost on foreign dividends	(1.90%)	0.40%	(1.00%)
U.S. state and local taxes	1.10%	(1.80%)	1.00%
U.S. deferred tax benefit on foreign income	(0.60%)	(3.10%)	(4.10%)
Asbestos charge	0.00%	19.10%	0.00%
Other	2.60%	2.30%	2.90%
Effective income tax rate	30.70%	27.50%	23.70%