Segment Information (Detail 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	$ 12,573	[1]	$ 9,521	[1]	$ 20,199	[1]	$ 16,038	[1]
Performance Materials [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	3,566	[1]	3,271	[1]	5,429	[1]	4,548	[1]
Industrial Filtration [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	2,198	[1]	0	[1]	2,984	[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	2,564	[1]	4,431	[1]	6,217	[1]	7,449	[1]
Thermal/Acoustical Fibers Segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	9,279	[1]	5,432	[1]	16,620	[1]	11,586	[1]
Other Products and Services [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	286	[1]	125	[1]	706	[1]	481	[1]
Corporate Office Expenses [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	$ (5,320)	[1]	$ (3,738)	[1]	$ (11,757)	[1]	$ (8,026)	[1]

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