Segment Information (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Segment Income Loss From Continuing Operations Before Provision For Income Tax [Line Items]
Income Loss From Continuing Operations Before Provision For Income Tax Segment	$ 215,892	$ 187,169	$ 396,655	$ 413,924
US 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	140,586	114,277	233,331	261,846
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	35,030	44,089	90,093	74,001
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	19,591	12,525	26,197	35,060
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	23,859	4,326	55,926	26,302
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	$ (3,174)	$ 11,952	$ (8,892)	$ 16,715