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Fair Value of Financial Instruments - Additional Information (Detail) (USD $)
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3 Months Ended | 12 Months Ended | 12 Months Ended | ||
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Dec. 31, 2011
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Dec. 31, 2011
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Dec. 31, 2012
Significant Other Observable Inputs (Level 2) [Member]
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Dec. 31, 2011
Significant Other Observable Inputs (Level 2) [Member]
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Dec. 31, 2011
U.S. Drilling [Member]
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| Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] | |||||
| Carrying amount of interest rate swap agreements | $ 100,000 | $ 100,000 | |||
| Carrying value of assets | 339,500,000 | 339,500,000 | 339,500,000 | ||
| Fair value | 169,500,000 | 169,500,000 | 169,500,000 | ||
| Impairments and other charges | $ 170,000,000 | $ 170,000,000 | $ 170,000,000 |
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- Definition
Carrying Value Of Assets Impaired No definition available.
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- Definition
Fair Value Of Assets Impaired No definition available.
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- Definition
The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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