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Number of arbitrations against third parties relating to a possible gain contingency.

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Represents the number of FlexRigs that the entity has to build and operate under separate drilling contracts.

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The amount as of the balance sheet date that the entity agreed to spend to satisfy the terms of disclosed arrangements in which the entity has agreed to purchase equipment, parts and supplies.

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The total of future contractually required payments on leases defined as operating.

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COMMITMENTS AND CONTINGENCIES (Details) (USD $)	12 Months Ended			1 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) (USD $)	Sep. 30, 2011 Unit USDPerRight D M Right multiple Arbitration SquareFoot Plan Y Rig	Sep. 30, 2010	Sep. 30, 2009	Nov. 30, 2011 Agreements Rig
Commitments and Contingencies
Number of new FlexRigs to build and operate (in rigs)	58			17
Number of new FlexRigs under construction (in rigs)				47
Purchase orders outstanding for drilling equipment	$ 361,300,000
Area of leased office space (in square feet)	135,000
Fiscal Year
2012	5,979,000
2013	4,557,000
2014	2,524,000
2015	2,343,000
2016	1,961,000
Thereafter	6,489,000
Total	23,853,000
Total rent expense	5,800,000	5,400,000	5,200,000
Number of arbitrations against third parties	2
Possible recovery relating to seizure of property in Venezuela	$ 75,000,000