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Asset Impairment Charges - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Indefinite-lived Intangible Assets [Line Items] |  |  |
Non-cash asset impairment charge |  |  | $ 1,200,000
Dresden Papier GmbH [Member] | Tradename [Member] |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |
Non-cash asset impairment charge | $ 0 | $ 0 | $ 1,200,000

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- Definition Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 + Details
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Balance Type: | debit
Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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