Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 199,830	$ 202,880
Operating profit (loss)	15,740	16,450
Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	80,960	80,110
Operating profit (loss)	16,850	17,840
Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	45,420	40,500
Operating profit (loss)	5,000	3,460
Energy [Member]
Segment Reporting Information [Line Items]
Net sales	40,930	44,750
Operating profit (loss)	(3,900)	(3,610)
Engineered Components [Member]
Segment Reporting Information [Line Items]
Net sales	32,520	37,520
Operating profit (loss)	4,980	5,580
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (7,190)	$ (6,820)