Segment Information Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Net sales	$ 222,420	$ 199,460	$ 648,140	$ 581,800
Operating profit (loss)	30,820	(108,320)	77,500	(106,640)
Operating Segments [Member] | Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	138,010	135,120	409,730	364,000
Operating profit (loss)	27,340	28,020	76,490	70,340
Operating Segments [Member] | Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	46,510	39,130	135,680	130,660
Operating profit (loss)	3,980	(133,500)	10,600	(132,630)
Operating Segments [Member] | Specialty Products [Member]
Segment Reporting Information [Line Items]
Net sales	37,900	25,210	102,730	87,140
Operating profit (loss)	6,660	3,380	17,190	870
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (7,160)	$ (6,220)	$ (26,780)	$ (45,220)