Purchased Intangible Assets and Goodwill (Changes in Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Roll Forward]
Goodwill	$ 181,447	$ 184,215
Accumulated impairment losses	(14,875)	(14,875)
Goodwill, net beginning balance	166,572	169,340
Other	0	(2,768)
Goodwill	181,447	181,447
Accumulated impairment losses	(14,875)	(14,875)
Goodwill, net ending balance	166,572	166,572
Glass Operations
Goodwill [Roll Forward]
Goodwill	164,457	164,457
Accumulated impairment losses	(9,434)	(9,434)
Goodwill, net beginning balance	155,023	155,023
Other	0	0
Goodwill	164,457	164,457
Accumulated impairment losses	(9,434)	(9,434)
Goodwill, net ending balance	155,023	155,023
Other Operations
Goodwill [Roll Forward]
Goodwill	16,990	19,758
Accumulated impairment losses	(5,441)	(5,441)
Goodwill, net beginning balance	11,549	14,317
Other	0	(2,768)
Goodwill	16,990	16,990
Accumulated impairment losses	(5,441)	(5,441)
Goodwill, net ending balance	$ 11,549	$ 11,549