Retirement Plans - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Other Postretirement Benefits Expense (Reversal of Expense), Noncash	$ 0.6	$ 0.5

Amount of noncash expense (reversal of expense) for other postretirement benefits. Excludes pension benefits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Name:	us-gaap_OtherPostretirementBenefitsExpenseReversalOfExpenseNoncash
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration