Segment Information (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Segment reporting information
Net sales	$ 404,354,000	$ 416,493,000	$ 1,186,399,000	$ 1,211,249,000
Energy and related sales, net	1,867,000	2,840,000	5,358,000	7,887,000
Total revenues	406,221,000	419,333,000	1,191,757,000	1,219,136,000
Costs of products sold	347,029,000	364,417,000	1,030,717,000	1,066,553,000
Gross profit (loss)	59,192,000	54,916,000	161,040,000	152,583,000
SG&A	29,380,000	31,430,000	89,460,000	94,520,000
Gains on dispositions of plant, equipment and timberlands, net	(1,473,000)	(698,000)	(8,471,000)	(3,902,000)
Total operating income (loss)	31,285,000	24,184,000	80,051,000	61,965,000
Other non-operating income (expense)	(4,050,000)	(6,459,000)	(11,953,000)	(19,291,000)
Income (loss) before income taxes	27,235,000	17,725,000	68,098,000	42,674,000
Supplementary Data
Net tons sold	250,900,000	246,700,000	724,200,000	726,900,000
Depreciation, depletion and amortization	17,100,000	17,500,000	51,123,000	51,779,000
Capital expenditures	14,400,000	16,800,000	45,000,000	44,600,000
Specialty Papers [Member]
Segment reporting information
Net sales	232,600,000	225,400,000	670,500,000	662,600,000
Energy and related sales, net	1,900,000	2,800,000	5,400,000	7,900,000
Total revenues	234,500,000	228,200,000	675,900,000	670,500,000
Costs of products sold	199,100,000	198,600,000	585,200,000	592,500,000
Gross profit (loss)	35,400,000	29,600,000	90,700,000	78,000,000
SG&A	14,000,000	12,600,000	41,300,000	38,900,000
Gains on dispositions of plant, equipment and timberlands, net
Total operating income (loss)	21,400,000	17,000,000	49,400,000	39,100,000
Other non-operating income (expense)
Income (loss) before income taxes	21,400,000	17,000,000	49,400,000	39,100,000
Supplementary Data
Net tons sold	204,500,000	199,600,000	587,100,000	590,100,000
Depreciation, depletion and amortization	9,200,000	9,200,000	27,100,000	26,700,000
Capital expenditures	5,400,000	6,700,000	19,100,000	20,000,000
Composite Fibers [Member]
Segment reporting information
Net sales	110,800,000	124,900,000	331,400,000	356,500,000
Energy and related sales, net
Total revenues	110,800,000	124,900,000	331,400,000	356,500,000
Costs of products sold	91,200,000	104,600,000	273,500,000	295,100,000
Gross profit (loss)	19,700,000	20,300,000	57,900,000	61,300,000
SG&A	9,400,000	10,200,000	28,800,000	29,600,000
Gains on dispositions of plant, equipment and timberlands, net
Total operating income (loss)	10,300,000	10,100,000	29,100,000	31,700,000
Other non-operating income (expense)
Income (loss) before income taxes	10,300,000	10,100,000	29,100,000	31,700,000
Supplementary Data
Net tons sold	23,500,000	24,100,000	69,200,000	70,000,000
Depreciation, depletion and amortization	5,700,000	6,200,000	17,600,000	18,700,000
Capital expenditures	7,500,000	5,700,000	22,900,000	16,200,000
Advanced Airlaid Materials [Member]
Segment reporting information
Net sales	60,900,000	66,200,000	184,500,000	192,200,000
Energy and related sales, net
Total revenues	60,900,000	66,200,000	184,500,000	192,200,000
Costs of products sold	54,100,000	59,200,000	164,300,000	174,300,000
Gross profit (loss)	6,800,000	7,000,000	20,200,000	17,900,000
SG&A	2,200,000	2,900,000	7,200,000	8,300,000
Gains on dispositions of plant, equipment and timberlands, net
Total operating income (loss)	4,600,000	4,100,000	13,000,000	9,600,000
Other non-operating income (expense)
Income (loss) before income taxes	4,600,000	4,100,000	13,000,000	9,600,000
Supplementary Data
Net tons sold	22,800,000	23,100,000	67,900,000	66,900,000
Depreciation, depletion and amortization	2,100,000	2,100,000	6,500,000	6,400,000
Capital expenditures	1,400,000	4,300,000	2,800,000	8,400,000
Other and Unallocated [Member]
Segment reporting information
Net sales
Energy and related sales, net
Total revenues
Costs of products sold	2,600,000	2,000,000	7,700,000	4,600,000
Gross profit (loss)	(2,600,000)	(2,000,000)	(7,800,000)	(4,600,000)
SG&A	3,900,000	5,700,000	12,200,000	17,700,000
Gains on dispositions of plant, equipment and timberlands, net	(1,500,000)	(700,000)	(8,500,000)	(3,900,000)
Total operating income (loss)	(5,000,000)	(7,000,000)	(11,500,000)	(18,400,000)
Other non-operating income (expense)	(4,100,000)	(6,500,000)	(12,000,000)	(19,300,000)
Income (loss) before income taxes	(9,000,000)	(13,400,000)	(23,400,000)	(37,700,000)
Supplementary Data
Net tons sold
Depreciation, depletion and amortization
Capital expenditures	$ 100,000		$ 200,000