XML 23 R43.htm IDEA: XBRL DOCUMENT
v2.3.0.15

Property and Equipment - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 9 Months Ended
--- | ---
Sep. 30, 2011 Rigs | Sep. 30, 2010 Rigs
Property, Plant, and Equipment Disclosure [Line Items] |  |
Number of drilling rigs that would no longer be marketed as rigs | 22 | 4
Impairment charges on drilling rigs | $ 4.3 | $ 4.2

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- Definition Number of Rigs + Details
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- Definition The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230 + Details
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