Segment Information - Operating Income by Segment (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income		$ 19,844	$ 15,522	$ 34,799	$ 29,201
Operating Segments | Performance Materials
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income		3,864	4,681	5,453	6,819
Operating Segments | Technical Nonwovens
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income	[1]	6,535	3,219	11,203	7,145
Operating Segments | Thermal/Acoustical Metals
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income		3,174	4,082	5,617	7,639
Operating Segments | Thermal/Acoustical Fibers
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income		12,157	10,630	24,446	20,954
Corporate Office Expenses
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Operating Income		$ (5,886)	$ (7,090)	$ (11,920)	$ (13,356)

[1] The Technical Nonwovens segment reports results of Texel and Gutsche for the period following the dates of acquisition of July 7, 2016 and December 31, 2016, respectively.