Number Of Drilling Units

No definition available.

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of interest capitalized, including amount of allowance for funds used during construction.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 835

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6501662&loc=d3e56162-110433

+ Details

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Details

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Property and Equipment (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
Property and Equipment (Narrative) (Details) (USD $)	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Property, Plant and Equipment [Line Items]
Interest capitalized	$ 8,200,000	$ 9,800,000	$ 23,700,000	$ 25,800,000
Construction in Progress, Newbuild Drilling Units [Member]
Property, Plant and Equipment [Line Items]
Expenditure towards construction of drilling units currently under construction	560,000,000		560,000,000
Number of drilling units	4		4
Capital Addition Purchase Commitments [Member] \| Construction in Progress, Newbuild Drilling Units [Member]
Property, Plant and Equipment [Line Items]
Commitments on drilling units under construction			$ 1,600,000,000