Total number of rigs evaluated for impairment in accordance with ASC 360 during the period.

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- Definition

Number of rigs for which indicators of impairment are not present. Therefore asset was not evaluated for impairment in accordance with ASC 360.

+ References

No definition available.

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- Definition

Schedule Of Asset Impairment Charges [Line Items]

+ 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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- Definition

A description of how an entity determined the fair value of the long-lived asset they are holding and using, for example, whether based on a quoted market price, prices for similar assets, or another valuation technique.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.CC)
-URI http://asc.fasb.org/extlink&oid=27011434&loc=d3e125687-122742

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Impairment of Assets - Additional Information (Detail)	3 Months Ended	9 Months Ended	12 Months Ended
Impairment of Assets - Additional Information (Detail)	Sep. 30, 2019 USD ($) Rig	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Schedule Of Asset Impairment Charges [Line Items]
Loss on impairment of assets		$ 27,225,000
Number of rigs not evaluated for impairment \| Rig	10
2019 Impaired Rigs [Member]
Schedule Of Asset Impairment Charges [Line Items]
Number of rigs evaluated for impairment \| Rig	3
Loss on impairment of assets	$ 0
2018 Impaired Rigs [Member]
Schedule Of Asset Impairment Charges [Line Items]
Loss on impairment of assets			$ 27,200,000
Impaired long-lived assets held and used, method for determining fair value			We estimated the fair value of the impaired jack-up rig using a market approach based on a signed agreement to sell the rig, less estimated costs to sell. We considered this valuation approach to be a Level 3 fair value measurement due to the level of estimation involved as the sale had not yet been completed at the time of our analysis.