Summary of Significant Accounting Policies (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Summary of Significant Accounting Policies (Textual) [Abstract]
Investments in unconsolidated affiliates accounted for using equity method	$ 371.0	$ 265.8
Investments in unconsolidated affiliates accounted for using cost method		1.9	0.9
Assets held for sale include investments in unconsolidated affiliates accounted for using the equity method	13.7	79.5
Fair Value of Equity Security investment	5.9	7.4
Impairment charges of oil and gas related assets		192.2
Capitalized cost discounted of unproved properties	10.00%
Impairment charges for unconsolidated oil and gas joint ventures	15.6		237.1
Equity Interest acquired	50.00%
Percentage in excess of fair value over carrying value	20.00%
Goodwill for the consolidated company, expected to be deductible for tax purposes	$ 12.9
Deferral of disclosure requirements provided by FASB regarding change to definition of oil and gas activities	1
Other Rigs [Member]
Property, Plant and Equipment [Line Items]
Operating rig asset depreciable life, operating days	4,900
Non-operating rig asset depreciable life	20
Jack Up Rigs [Member]
Property, Plant and Equipment [Line Items]
Operating rig asset depreciable life, operating days	8,030
Non-operating rig asset depreciable life	30
Building [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, Minimum	10
Estimated useful life, Maximum	30
Well Servicing Rigs [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, Minimum	3
Estimated useful life, Maximum	15
Marine transportation and supply vessels [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, Minimum	10
Estimated useful life, Maximum	25
Oilfield Hauling and Mobile Equipment and Other Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, Minimum	3
Estimated useful life, Maximum	10