Income Taxes (Schedule of Earnings (Losses) Before Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income (Loss) From Continuing Operations Before Income Taxes, Minority Interest, And Income (Loss) From Equity Method Investments [Line Items]
Income before income taxes	$ 50,377	$ 155,530	$ 50,365
United States [Member]
Income (Loss) From Continuing Operations Before Income Taxes, Minority Interest, And Income (Loss) From Equity Method Investments [Line Items]
Income before income taxes	60,166	157,215	50,406
Canada [Member]
Income (Loss) From Continuing Operations Before Income Taxes, Minority Interest, And Income (Loss) From Equity Method Investments [Line Items]
Income before income taxes	(7,690)	(2,632)	(41)
Other [Member]
Income (Loss) From Continuing Operations Before Income Taxes, Minority Interest, And Income (Loss) From Equity Method Investments [Line Items]
Income before income taxes	$ (2,099)	$ 947	$ 0