Segment Information (Income Loss Before Provision for Income Tax of Reportable Segments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	$ 199,440	$ 278,827
US Traditional Segment Reporting Information [Member]
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	50,972	79,543
US Non-Traditional Segment Reporting Information [Member]
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	83,124	97,564
Canada Segment Reporting Information [Member]
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	20,064	36,308
Europe And South Africa Segment Reporting Information [Member]
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	15,205	10,963
Asia Pacific Segment Reporting Information [Member]
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	26,311	18,242
Corporate And Other Segment Reporting Information [Member]
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	$ 3,764	$ 36,207