General Information (Details Textual)	3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Jun. 30, 2011 Drillships	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Dec. 31, 2010 USD ($) Rigs	Oct. 20, 2011	Sep. 30, 2011 Bonds Rigs Country	Sep. 30, 2011 Cold stacked jack-up rigs in U.S. Gulf of Mexico [Member] Rigs	Sep. 30, 2011 Independent-leg, cantilevered jack-up rig [Member] Rigs	Sep. 30, 2011 Mat-supported jack-up rig [Member] Rigs	Sep. 30, 2011 Cold stacked semisubmersible rigs [Member] Rigs	Sep. 30, 2011 Cold stacked rigs located in U.S. Gulf of Mexico [Member] Rigs	Sep. 30, 2011 Cold stacked rigs located in Malaysia [Member] Rigs
Property, Plant and Equipment [Line Items]
Number of cold stacked rigs by type of rig									4	1	3	4	2	2
General Information (Textual) [Abstract]
Net book value of cold stacked rigs	$ 87,600,000			$ 87,600,000		$ 78,000,000
Outstanding common stock owned by Loews Corporation							50.40%
Period considered to treat short-term, highly liquid investments as cash equivalents				Three months or less
Net foreign currency transaction gains (losses) (Note 5)	(1,400,000)	3,700,000		(4,600,000)	200,000
Initial term of contracts minimum months				2 months
Initial term of contracts maximum months				60 months
Amount of previously recorded U.S. income tax expense reversed in current period				15,000,000
Sum and probability of occurrence scenarios				100.00%
Reduction in assumed dayrates for the cold-stacked rigs				5.00%
Number of new drillships			3
Total number of cold stacked rigs						7		8
Gain (loss) on foreign currency transactions recognized in income	0	0		0	0
Qualifying expenditure					0
Amount capitalized for asset replacements and betterments				136,300,000		379,800,000
Range of asset project costs, lower limit				25,000		25,000
Range of asset project costs, upper limit				$ 50,000,000		$ 50,000,000