Litigation - Summary of Activity in Asbestos Insurance Recoveries (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Loss Contingencies [Line Items]
Insurance receivable – asbestos, beginning of the year	$ 152,508
Insurance receivable – asbestos, end of the period	150,093
Asbestos Claims [Member]
Loss Contingencies [Line Items]
Insurance receivable – asbestos, beginning of the year	152,508	$ 100,342
Settlement and defense costs paid by insurance carriers	(2,415)	(4,954)
Insurance receivable – asbestos, end of the period	$ 150,093	$ 95,388