Impairments and Other Charges (Details) (USD $) In Thousands, except Share data in Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011 rig	Dec. 31, 2010
Summary of Impairments and other charges
Provision for retirement of long-lived assets	$ 138,666	$ 98,072	$ 23,213
Intangible asset impairment	74,960
Goodwill impairments	26,279		10,707
Impairment of long-lived assets	50,355		27,372
Provision for termination payment		100,000
Total impairments and other charges	290,260	198,072	61,292
Number of Jackup rigs decommissioned and retired		1
Number of trucks and rigs retired		116
Number of common shares contributed as charity	1
Canada
Summary of Impairments and other charges
Provision for retirement of long-lived assets	33,700
Impairment of long-lived assets	32,900
US Production Services
Summary of Impairments and other charges
Provision for retirement of long-lived assets		8,900
U.S. Lower 48 Land Drilling
Summary of Impairments and other charges
Provision for retirement of long-lived assets	34,000	63,200
Impairment of long-lived assets	17,400
International
Summary of Impairments and other charges
Provision for retirement of long-lived assets	16,500	26,100
Goodwill impairments	19,000
U.S. Offshore
Summary of Impairments and other charges
Provision for retirement of long-lived assets	3,100
Goodwill impairments	7,300		10,700
Impairment of long-lived assets			27,300
Other Rig Services
Summary of Impairments and other charges
Provision for retirement of long-lived assets	2,000
Completion and Production Services
Summary of Impairments and other charges
Provision for retirement of long-lived assets	49,400
Trade Names
Summary of Impairments and other charges
Intangible asset impairment	$ 75,000
Lived intangible asset	10 years