Discontinued Operations - Summary of Discontinued Operations included in Condensed Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Non-operating income (expense)
Income (loss) before income taxes	$ (485)	$ (18,517)	$ 229	$ (14,058)
Income tax (provision) benefit	(23)	(9,838)	8	(8,831)
Income (loss) from discontinued operations	(462)	(8,679)	221	(5,227)
Specialty Papers [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Total revenues		190,975		391,842
Costs of products sold		202,671		391,192
Gross profit (loss)		(11,696)		650
Selling, general and administrative expenses	485	5,376	(229)	12,508
Gains on dispositions of plant, equipment and timberlands, net		(5)		(443)
Operating income (loss)	(485)	(17,067)	229	(11,415)
Non-operating income (expense)
Interest expense		(1,991)		(3,736)
Other, net		541		1,093
Income (loss) before income taxes	(485)	(18,517)	229	(14,058)
Income tax (provision) benefit	23	(9,838)	(8)	(8,831)
Income (loss) from discontinued operations	$ (462)	(8,679)	$ 221	(5,227)
Specialty Papers [Member] | Product [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Total revenues		190,031		389,469
Specialty Papers [Member] | Energy and Related Sales Net [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Total revenues		$ 944		$ 2,373