Segment Information Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Net sales	$ 199,460	$ 188,410	$ 581,800	$ 552,610
Operating profit (loss)	(108,320)	23,570	(106,640)	70,430
Operating Segments [Member] | Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	135,120	105,480	364,000	298,310
Operating profit (loss)	28,020	19,740	70,340	60,020
Operating Segments [Member] | Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	39,130	50,560	130,660	145,650
Operating profit (loss)	(133,500)	7,810	(132,630)	21,270
Operating Segments [Member] | Specialty Products [Member]
Segment Reporting Information [Line Items]
Net sales	25,210	32,370	87,140	108,650
Operating profit (loss)	3,380	3,620	870	13,730
Corporate, Non-Segment [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (6,220)	$ (7,600)	$ (45,220)	$ (24,590)