Litigation - Schedule of Loss Contingencies by Contingency (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2021 Claim Category	Sep. 30, 2020 Claim
Loss Contingencies [Line Items]
Number of claims inactive or transferred to MDL panel | Claim	661	711
Number of categories | Category	2
Minimum [Member]
Loss Contingencies [Line Items]
Administrative closures claims period	6 years