The carrying amount on the books of the entity of the impaired assets to be held for use or to be disposed of by sale.

No definition available.

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- Definition

Number of rigs with indications that their carrying amounts may not be recoverable, which we determined to be impaired.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
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- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The carrying amount on the books of the entity of the impaired asset to be disposed of by a method other than sale.

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

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Financial Instruments and Fair Value Disclosures - Assets and Liabilities Measured at Fair Value on Recurring and Nonrecurring Basis (Parenthetical) (Detail) $ in Thousands		3 Months Ended	9 Months Ended		12 Months Ended
	Dec. 31, 2016 USD ($) Rigs	Jun. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) Rigs	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on impairment of assets			$ 71,268	$ 678,145
Book value of physical assets	$ 5,726,935		5,432,689		$ 5,726,935
Carrying value of impaired assets	45,100				45,100
Asset held for sale	400		2,598		400
Rig Spare Parts and Supplies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on impairment of assets		$ 8,100			8,100
Carrying value of impaired assets	23,600				23,600
2016 Impaired Rigs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on impairment of assets		$ 670,000			670,000
Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on impairment of assets			71,268		678,145
Carrying value of impaired assets	$ 69,153		$ 2,000		69,153
Nonrecurring Fair Value Measurements [Member] \| Drilling Rigs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of rigs written down to their estimated recoverable amounts \| Rigs	11
Book value of physical assets	$ 45,500				45,500
Nonrecurring Fair Value Measurements [Member] \| Ultra-Deepwater Rigs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of rigs written down to their estimated recoverable amounts \| Rigs			1
Nonrecurring Fair Value Measurements [Member] \| Deepwater Semisubmersible Rigs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of rigs written down to their estimated recoverable amounts \| Rigs			1
Prepaid Expenses and Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of impaired assets	$ 23,600				$ 23,600