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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018
Income Tax [Line Items] |  |
Increase (decrease) in net deferred tax liability | $ 154.7 |
Deferred tax assets (liability) net | $ 81.0 | $ 73.7

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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Change during the period in carrying value for all deferred liabilities due within one year or operating cycle. + References 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 (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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