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Assets Held for Sale and Discontinued Operations - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
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Mar. 31, 2019 | Dec. 31, 2018
Discontinued Operations and Disposal Groups [Abstract] |  |
Incremental Non-Cash Charge | $ 36.6 |
Asset Impairment Charges | 285.0 | $ 321.6
Deferred Tax Assets, Goodwill and Intangible Assets | $ 36.6 |

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- Definition Amount of incremental non-cash charge on goodwill. + References No definition available. + Details
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Balance Type: | debit
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + 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 (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill. + References No definition available. + Details
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- References No definition available. + Details
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