Income Taxes - Deferred Taxes (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Other non-current assets	$ 27.4	$ 29.6
Deferred tax liabilities	107.4	104.4
Total deferred tax liabilities	$ 80.0	$ 74.8

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31931-109318

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31917-109318

Name:	us-gaap_DeferredIncomeTaxLiabilitiesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant