Certain Balance Sheet Components Capitalized Interest Narrative (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Construction in progress, including purchased equipment	$ 30,108,000		$ 26,097,000
Interest Costs Capitalized	43,000	0
Enterprise Resource Planning Software System [Member]
Property, Plant and Equipment [Line Items]
Construction in progress, including purchased equipment	12,300,000
Interest Costs Capitalized	$ 43,000