Segment Information - Consolidated Net Sales 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, Revenue Reconciling Item [Line Items]
Net sales		$ 174,879	$ 137,235	$ 340,366	$ 266,935
Operating Segments | Performance Materials
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		29,301	29,966	58,052	56,349
Operating Segments | Performance Materials | Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		19,255	18,657	38,100	35,816
Operating Segments | Performance Materials | Thermal Insulation
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		7,407	7,214	14,833	13,489
Operating Segments | Performance Materials | Life Sciences Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		2,639	4,095	5,119	7,044
Operating Segments | Technical Nonwovens
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	[1]	67,098	27,840	126,016	59,047
Operating Segments | Technical Nonwovens | Industrial Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	[1]	36,325	20,128	70,538	43,722
Operating Segments | Technical Nonwovens | Advanced Materials
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	[1],[2]	30,773	7,712	55,478	15,325
Operating Segments | Thermal/Acoustical Metals
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		43,385	45,245	87,665	87,242
Operating Segments | Thermal/Acoustical Metals | Metal parts
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		40,827	41,053	82,521	77,836
Operating Segments | Thermal/Acoustical Metals | Tooling
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		2,558	4,192	5,144	9,406
Operating Segments | Thermal/Acoustical Fibers
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		43,499	40,168	84,871	76,029
Operating Segments | Thermal/Acoustical Fibers | Fiber parts
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		40,704	36,934	81,691	72,611
Operating Segments | Thermal/Acoustical Fibers | Tooling
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales		2,795	3,234	3,180	3,418
Eliminations and Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	[2]	$ (8,404)	$ (5,984)	$ (16,238)	$ (11,732)

[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.

[2] Included in the Technical Nonwovens segment and Eliminations and Other is $6.8 million and $4.6 million in intercompany sales to the T/A Fibers segment for the quarters ended June 30, 2017 and 2016, respectively