Segment Information - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 220,811	$ 186,413	$ 438,836	$ 378,073
Operating income	13,179	12,249	22,229	26,285
Operating Segments \| Performance Materials
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	65,102	31,234	129,682	61,927
Operating income	3,303	3,649	4,762	6,290
Amortization of intangible assets	4,000		8,000
Operating Segments \| Performance Materials \| Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	24,732	23,061	48,666	46,203
Operating Segments \| Performance Materials \| Sealing and Advanced Solutions
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	40,370	8,173	81,016	15,724
Operating Segments \| Technical Nonwovens
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	69,078	71,712	134,684	139,253
Operating income	7,844	6,118	12,578	11,124
Operating Segments \| Technical Nonwovens \| Industrial Filtration
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	38,706	39,170	81,070	79,401
Operating Segments \| Technical Nonwovens \| Advanced Materials
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	30,372	32,542	53,614	59,852
Intercompany sales	4,600	5,800	9,300	12,900
Operating Segments \| Thermal Acoustical Solutions
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	93,272	90,169	187,585	191,606
Operating income	7,357	8,820	16,848	21,434
Operating Segments \| Thermal Acoustical Solutions \| Parts
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	85,705	82,920	170,281	171,041
Operating Segments \| Thermal Acoustical Solutions \| Tooling
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	7,567	7,249	17,304	20,565
Eliminations and Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	(6,641)	(6,702)	(13,115)	(14,713)
Intercompany sales	4,700	7,100	4,700	7,100
Corporate Office Expenses
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating income	$ (5,325)	$ (6,338)	$ (11,959)	$ (12,563)

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