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Commitments, Contingencies and Legal Proceedings - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017 USD ($) Operable_Unit	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Commitments Contingencies And Litigation [Line Items]
Annual payments due under operating leases	$ 37,600,000
Aggregate contractual obligation	$ 167,500,000
Number of operable units | Operable_Unit	5
Reserve for Environmental liabilities, current portion	$ 28,500,000	$ 25,000,000
Other Long-Term Liabilities [Member]
Commitments Contingencies And Litigation [Line Items]
Reserve for Environmental liabilities, remaining portion	14,600,000
NCR/Appvion Consent Decree [Member]
Commitments Contingencies And Litigation [Line Items]
Contribution payment towards remedial action and natural resource damages	75,000,000
Anticipated cost to complete work for remaining site remedy	200,000,000
Expected payments for governments unreimbursed past costs which are under dispute			$ 34,000,000
Unreimbursed costs			0
Unspent settlement money			4,000,000
NADAR [Member]
Commitments Contingencies And Litigation [Line Items]
Expected payments for governments unreimbursed past costs which are under dispute	104,000,000
Unspent settlement money	60,000,000
Georgia Pacific [Member]
Commitments Contingencies And Litigation [Line Items]
Settlement payable amount	$ 9,500,000
Payment due date	2017-08
Maximum [Member]
Commitments Contingencies And Litigation [Line Items]
NCR costs and damages percentage	100.00%
Maximum [Member] | NCR/Appvion Consent Decree [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated cost related to Fox River matter	$ 30,000,000
Minimum [Member] | December 2009 - Long Term Monitoring Plan [Member]
Commitments Contingencies And Litigation [Line Items]
Period over which cash expenditure to be incurred for monitoring activities	30 years
Minimum [Member] | GLT, GP and NCR [Member] | NCR/Appvion Consent Decree [Member]
Commitments Contingencies And Litigation [Line Items]
Contribution payment towards remedial action and natural resource damages	$ 1,000,000,000
OU2-5 [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated future cost of cleanup work		$ 13,400,000	$ 13,400,000
Expected cleanup work continuation year	through 2019
NCR costs and damages percentage	100.00%
OU2-5 [Member] | Whiting Litigation [Member]
Commitments Contingencies And Litigation [Line Items]
NCR costs and damages percentage	100.00%

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The specific areas of the site into which the contaminated area has been separated by the US EPA.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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