Segment Information Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Net sales	$ 199,550	$ 190,830	$ 382,340	$ 364,200
Operating profit (loss)	(18,150)	27,060	1,680	46,860
Operating Segments [Member] | Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	128,830	103,990	228,880	192,830
Operating profit (loss)	24,040	22,640	42,320	40,280
Operating Segments [Member] | Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	42,610	49,510	91,530	95,090
Operating profit (loss)	(4,210)	7,650	870	13,460
Operating Segments [Member] | Specialty Products [Member]
Segment Reporting Information [Line Items]
Net sales	28,110	37,330	61,930	76,280
Operating profit (loss)	(5,940)	5,410	(2,510)	10,110
Corporate, Non-Segment [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (32,040)	$ (8,640)	$ (39,000)	$ (16,990)