Segment Information Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Net sales	$ 182,790	$ 173,370
Operating profit (loss)	19,830	19,800
Operating Segments [Member] | Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	100,050	88,840
Operating profit (loss)	18,280	17,640
Operating Segments [Member] | Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	48,920	45,580
Operating profit (loss)	5,080	5,810
Operating Segments [Member] | Specialty Products [Member]
Segment Reporting Information [Line Items]
Net sales	33,820	38,950
Operating profit (loss)	3,430	4,700
Corporate, Non-Segment [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (6,960)	$ (8,350)