Reportable Segments (Schedule of Financial Data by Reporting Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Net sales	$ 183,147	$ 194,589	$ 567,775	$ 566,606
Operating income/(loss)	13,255	23,112	32,260	(63,801)
Other expense/ (income), net	2,692	3,069	5,637	5,062
(Loss)/income before income taxes	7,079	16,046	15,567	(81,473)
Operating Segments [Member] | Machine Clothing [Member]
Segment Reporting Information [Line Items]
Net sales	162,864	177,471	507,809	518,881
Operating income/(loss)	33,196	44,918	96,803	120,760
Operating Segments [Member] | Engineered Composites [Member]
Segment Reporting Information [Line Items]
Net sales	20,283	17,118	59,966	47,725
Operating income/(loss)	(572)	(312)	(4,460)	(653)
Research Expense [Member]
Segment Reporting Information [Line Items]
Operating income/(loss)	(7,418)	(6,734)	(22,082)	(20,052)
Unallocated Expenses [Member]
Segment Reporting Information [Line Items]
Operating income/(loss)	(11,951)	(14,760)	(38,001)	(163,856)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Interest income	(351)	(395)	(951)	(1,000)
Interest expense	3,835	4,392	12,007	13,610
Other expense/ (income), net	$ 2,692	$ 3,069	$ 5,637	$ 5,062