Other non-current assets (Table) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Other non-current assets (Abstract)
Security deposits for derivatives	$ 0	$ 33,100
Option for construction of drillships	24,756	24,756
Deferred mobilization expenses	59,496	24,176
Other	17,734	9,049
Balance at end of year/period	$ 101,986	$ 91,081

Non current portion of deferred mobilization expenses.

No definition available.

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- Definition

Amount paid as at the balance sheet date for the acquisition of option for future construction of drillships and rigs.

+ References

No definition available.

+ Details

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- Definition

The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

+ References

+ Details

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- Definition

Carrying amount as of the balance sheet date of noncurrent assets which have not been itemized or categorized in the footnotes to the financial statements and are a component of Other Assets, Noncurrent (OtherAssetsNoncurrent). Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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- Definition

Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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