Discontinued Operations - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Oct. 31, 2018	Oct. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (loss)			$ (177,156)	$ 13,526	$ 35,731
Pension Benefits [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Related assets transferred from existing pension plan			25,700	27,900
Pension Benefits [Member] | Reclassifications Out of Accumulated Other Comprehensive Income [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (loss)			75,996	15,105	23,175
Pension Benefits [Member] | Curtailment and Settlement Recognition [Member] | Reclassifications Out of Accumulated Other Comprehensive Income [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (loss)			54,000
Specialty Papers [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Selling price of business unit	$ 360,000	$ 360,000
Cash proceeds from divestiture of business		323,000
Retiree healthcare liabilities	38,000	38,000
Pension liabilities assumed	210,000	210,000
Related assets transferred from existing pension plan	$ 280,000	$ 280,000
Impairment charge			144,124
Income (loss)			$ (177,156)	$ 13,526	$ 35,731