Derivatives And Risk Management (Foreign Currency Exchange Contracts) (Details) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 United States of America, Dollars [Member] USD ($)	Dec. 31, 2011 United States of America, Dollars [Member] USD ($)	Dec. 31, 2012 Canada, Dollars [Member] CAD	Dec. 31, 2011 Canada, Dollars [Member] CAD
Intercompany Foreign Currency Balance [Line Items]
Notional amount			$ 12,621	$ 7,033	12,502	7,192
Number of contracts	20	28
Number of days Canadian currency prices are settled with U.S. dollars	60 days