Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Net sales	$ 224,900	$ 224,710	$ 449,030	$ 441,540
Operating profit (loss)	19,210	25,370	42,230	49,480
Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	89,580	86,250	168,540	167,680
Operating profit (loss)	20,710	20,540	38,220	38,900
Energy [Member]
Segment Reporting Information [Line Items]
Net sales	50,150	52,320	101,310	105,100
Operating profit (loss)	(7,170)	(630)	(6,830)	1,970
Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	43,220	31,820	88,960	59,010
Operating profit (loss)	7,220	5,660	15,300	10,520
Engineered Components [Member]
Segment Reporting Information [Line Items]
Net sales	41,950	54,320	90,220	109,750
Operating profit (loss)	6,220	8,950	12,190	16,830
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (7,770)	$ (9,150)	$ (16,650)	$ (18,740)