Segment Information (Reconciliation of Depreciation and Amortization from Segment to Consolidated) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	$ 1,151,088	$ 1,087,579	$ 1,192,517
US Traditional Segment Reporting Information [Member]
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	558,404	564,359	555,875
US Non-Traditional Segment Reporting Information [Member]
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	232,348	213,745	225,910
Canada Segment Reporting Information [Member]
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	204,229	193,878	182,914
Europe [Member]
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	57,291	55,003	69,002
Asia Pacific [Member]
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	95,172	57,104	154,776
Corporate Segment [Member]
Depreciation, Depletion and Amortization [Abstract]
Depreciation, Depletion and Amortization, Nonproduction	$ 3,644	$ 3,490	$ 4,040