Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance, beginning	$ 316,650	$ 319,390
Goodwill, Other Changes	18,400
Goodwill reassigned between segments	0
Foreign currency translation	(410)	(2,740)
Balance, ending	334,640	316,650
Packaging [Member]
Goodwill [Roll Forward]
Balance, beginning	163,660	166,400
Goodwill, Acquired During Period	18,400
Goodwill reassigned between segments	0
Foreign currency translation	(410)	(2,740)
Balance, ending	181,650	163,660
Aerospace [Member]
Goodwill [Roll Forward]
Balance, beginning	146,430	146,430
Goodwill, Other Changes	0
Goodwill reassigned between segments	(12,740)
Foreign currency translation	0	0
Balance, ending	133,690	146,430
Specialty Products [Member]
Goodwill [Roll Forward]
Balance, beginning	6,560	6,560
Goodwill, Acquired During Period	0
Goodwill reassigned between segments	12,740
Foreign currency translation	0	0
Balance, ending	$ 19,300	$ 6,560