Segment Information - Consolidated Net Sales by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 186,413	$ 174,879	$ 378,073	$ 340,366
Operating Segments | Performance Materials
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	31,234	29,301	61,927	58,052
Operating Segments | Performance Materials | Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	20,574	19,255	41,264	38,100
Operating Segments | Performance Materials | Thermal Insulation
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	7,796	7,407	15,303	14,833
Operating Segments | Performance Materials | Life Sciences Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	2,864	2,639	5,360	5,119
Operating Segments | Technical Nonwovens
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	71,712	67,098	139,253	126,016
Operating Segments | Technical Nonwovens | Industrial Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	39,170	36,325	79,401	70,538
Operating Segments | Technical Nonwovens | Advanced Materials
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	32,542	30,773	59,852	55,478
Operating Segments | Thermal Acoustical Solutions
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	90,169	86,002	191,606	170,787
Operating Segments | Thermal Acoustical Solutions | Parts
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	82,920	80,648	171,041	162,462
Operating Segments | Thermal Acoustical Solutions | Tooling
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	7,249	5,354	20,565	8,325
Eliminations and Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ (6,702)	$ (7,522)	$ (14,713)	$ (14,489)