Reportable Segments and Geographic Data (Schedule of Financial Data by Reporting Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Net sales	$ 189,600	$ 183,100	$ 198,000	$ 186,700	$ 194,300	$ 194,600	$ 191,900	$ 180,100	$ 197,400	$ 200,300	$ 189,700	$ 200,000	$ 757,414	$ 760,941	$ 787,287
Depreciation and amortization													63,789	63,067	63,812
Operating income/(loss)													52,091	(44,136)	74,608
Interest income													(1,468)	(1,517)	(2,027)
Interest expense													15,227	18,118	20,148
Other expense/ (income), net													7,256	7,629	2,639
Income/(loss) before income taxes													31,076	(68,366)	53,848
Machine Clothing [Member]
Segment Reporting Information [Line Items]
Net sales													674,747	693,176	739,211
Depreciation and amortization													45,237	46,843	48,181
Operating income/(loss)													136,698	163,873	176,759
Engineered Composites [Member]
Segment Reporting Information [Line Items]
Net sales													82,667	67,765	48,076
Depreciation and amortization													7,640	5,920	4,959
Operating income/(loss)													(2,974)	(840)	(4,204)
Research Expense [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization													2,104	1,252	1,314
Operating income/(loss)													(30,220)	(27,616)	(29,007)
Unallocated Expenses [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization													8,808	9,052	9,358
Operating income/(loss)													(51,413)	(179,553)	(68,940)
Significant Reconciling Items [Member]
Segment Reporting Information [Line Items]
Interest income													(1,468)	(1,517)	(2,027)
Interest expense													15,227	18,118	20,148
Other expense/ (income), net													$ 7,256	$ 7,629	$ 2,639