Segment Information (Detail 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	$ 5,779	[1]	$ 7,386	[1]	$ 25,978	[1]	$ 23,424	[1]
Performance Materials [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	2,272	[1]	2,419	[1]	7,701	[1]	6,967	[1]
Industrial Filtration [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	1,833	[1]	0	[1]	4,817	[1]	0	[1]
Thermal/Acoustical Metals Segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	4,267	[1]	3,742	[1]	10,484	[1]	11,191	[1]
Thermal/Acoustical Fibers Segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	6,911	[1]	5,206	[1]	23,531	[1]	16,792	[1]
Other Products and Services [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	537	[1]	112	[1]	1,243	[1]	593	[1]
Corporate Office Expenses [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	$ (10,041)	[1]	$ (4,093)	[1]	$ (21,798)	[1]	$ (12,119)	[1]

[1] Industrial Filtration segment reports results for the period following the date of acquisition of February 20, 2014 through September 30, 2014.