Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2017

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill and Other Intangible Assets

The following table sets forth information with respect to goodwill and other intangible assets:

	December 31
In thousands		2017			2016
Goodwill – Composite Fibers	$	82,744		$	73,094
Specialty Papers
Customer relationships	$	6,155		$	6,155
Composite Fibers
Tradename		4,773			4,195
Technology and related		40,686			35,874
Customer relationships and related		36,705			32,310
Advanced Airlaid Materials
Technology and related		1,488			1,377
Customer relationships and related		3,001			2,638
Total intangibles		92,808			82,549
Accumulated amortization		(33,949	)		(26,290	)
Net intangibles	$	58,859		$	56,259

Summary of Amortization of Intangible Assets

amortized over periods ranging from 14 years to 20 years. The following table sets forth information pertaining to amortization of intangible assets:

In thousands			2017		2016		2015
Aggregate amortization    expense:		$	4,773	$	4,852	$	5,340
Estimated amortization    expense:
	2018		4,773
	2019		4,773
	2020		4,639
	2021		4,254
	2022		4,139