Accumulated Other Comprehensive Income (Loss) (Schedule Of Reclassifications Of Balances Out Of Accumulated Other Comprehensive Income (Loss) Into Net Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	$ (189,431)	$ (190,694)
Total, before taxes	14,649	13,087
Income tax expense (benefit)	4,779	4,608
Total, net of tax	9,870	8,479
Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total, before taxes	(33)	(37)
Income tax expense (benefit)	(13)	(14)
Total, net of tax	(20)	(23)
Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments | Aluminum Futures Contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	(48)	(37)
Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments | Foreign Currency Forward Contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	15	0
Reclassification Out Of Accumulated Other Comprehensive Income | Pension & Other Post-retirement Benefit Adjust.
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Actuarial gain (loss) and prior service costs, before taxes	(3,984)	(2,737)
Income tax expense (benefit)	(1,462)	(997)
Total, net of tax	$ (2,522)	$ (1,740)