Segment Information - Schedule of Financial and Other Information by Business Unit (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) T	Jun. 30, 2016 USD ($) T	Jun. 30, 2017 USD ($) T	Jun. 30, 2016 USD ($) T
Segment Reporting Information [Line Items]
Net sales	$ 387,342	$ 406,413	$ 778,055	$ 808,631
Energy and related sales, net	981	2,001	2,110	2,667
Total revenues	388,323	408,414	780,165	811,298
Cost of products sold	357,887	365,691	692,800	710,732
Gross profit	30,436	42,723	87,365	100,566
SG&A	31,999	37,191	67,085	69,049
(Gains) losses on dispositions of plant, equipment and timberlands, net	(58)	2	(26)	26
Operating income (loss)	(1,505)	5,530	20,306	31,491
Non-operating expense	(4,580)	(3,575)	(8,754)	(8,300)
(Loss) income before income taxes	$ (6,085)	$ 1,955	$ 11,552	$ 23,191
Supplementary Data
Net tons sold | T	251,500	259,700	512,400	527,000
Depreciation, depletion and amortization	$ 17,700	$ 16,800	$ 34,967	$ 33,411
Capital expenditures	34,300	37,100	71,000	80,400
Composite Fibers [Member]
Segment Reporting Information [Line Items]
Net sales	133,100	136,400	258,200	259,900
Total revenues	133,100	136,400	258,200	259,900
Cost of products sold	107,600	109,000	207,200	210,300
Gross profit	25,500	27,400	51,000	49,600
SG&A	10,800	12,100	21,900	23,200
Operating income (loss)	14,700	15,300	29,100	26,400
(Loss) income before income taxes	$ 14,700	$ 15,300	$ 29,100	$ 26,400
Supplementary Data
Net tons sold | T	41,900	40,700	80,700	77,600
Depreciation, depletion and amortization	$ 7,000	$ 7,200	$ 13,800	$ 14,300
Capital expenditures	2,100	2,300	6,800	8,600
Advanced Airlaid Materials [Member]
Segment Reporting Information [Line Items]
Net sales	62,800	60,800	122,700	121,500
Total revenues	62,800	60,800	122,700	121,500
Cost of products sold	53,000	51,800	103,500	104,100
Gross profit	9,800	9,000	19,200	17,400
SG&A	2,300	2,200	4,600	4,200
Operating income (loss)	7,500	6,800	14,600	13,200
(Loss) income before income taxes	$ 7,500	$ 6,800	$ 14,600	$ 13,200
Supplementary Data
Net tons sold | T	25,500	24,400	50,300	48,900
Depreciation, depletion and amortization	$ 2,300	$ 2,400	$ 4,600	$ 4,700
Capital expenditures	12,900	6,100	23,500	20,700
Specialty Papers [Member]
Segment Reporting Information [Line Items]
Net sales	191,400	209,300	397,100	427,200
Energy and related sales, net	1,000	2,000	2,100	2,700
Total revenues	192,400	211,300	399,200	429,900
Cost of products sold	195,900	202,900	376,000	394,000
Gross profit	(3,500)	8,400	23,200	35,900
SG&A	10,300	14,200	23,800	26,600
Operating income (loss)	(13,800)	(5,800)	(600)	9,300
(Loss) income before income taxes	$ (13,800)	$ (5,800)	$ (600)	$ 9,300
Supplementary Data
Net tons sold | T	184,100	194,700	381,400	400,500
Depreciation, depletion and amortization	$ 7,700	$ 6,500	$ 14,900	$ 13,200
Capital expenditures	15,800	28,700	34,000	50,800
Other and Unallocated [Member]
Segment Reporting Information [Line Items]
Cost of products sold	1,400	2,000	6,100	2,300
Gross profit	(1,400)	(2,000)	(6,100)	(2,300)
SG&A	8,600	8,700	16,800	15,000
(Gains) losses on dispositions of plant, equipment and timberlands, net	(100)
Operating income (loss)	(9,900)	(10,700)	(22,900)	(17,300)
Non-operating expense	(4,600)	(3,600)	(8,800)	(8,300)
(Loss) income before income taxes	(14,500)	(14,300)	(31,700)	(25,600)
Supplementary Data
Depreciation, depletion and amortization	700	$ 700	1,700	1,200
Capital expenditures	$ 3,500		$ 6,700	$ 300