Litigation - Schedule of Loss Contingencies by Contingency (Detail) - Asbestos Claims [Member]	6 Months Ended
	Jun. 30, 2021 USD ($) Claim	Jun. 30, 2020 USD ($) Claim
Loss Contingencies [Line Items]
Total claims pending at the beginning of the period	5,891	6,102
New claims served	642	492
Claims dismissed	(272)	(181)
Claims settled	(197)	(159)
Total claims pending at the end of period	6,064	6,254
Administrative closures	(2,905)
Total active claims at the end of the period	3,159
Gross settlement and defense costs paid in period | $	$ 9,420,000	$ 16,221,000
Avg. gross settlement and defense costs per claim resolved | $	$ 20,090.00	$ 47,710