Derivative Financial Instruments (Schedule Of Derivative Instruments Effect On Other Comprehensive Income (Loss) ) (Details) (Cash Flow Derivative Hedges [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Aluminum Futures Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gain (loss) recognized in other comprehensive income	$ (617)	$ (478)	$ (1,317)	$ (242)
Aluminum Futures Contracts [Member] | Cost Of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gain (loss) reclassified from accumulated other comprehensive income to net income (effective portion)	(600)	55	(902)	641
Foreign Currency Forwards And Options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gain (loss) recognized in other comprehensive income	$ 1,132		$ 1,132