Aggregate cost of asset replacement and betterment projects, which have been capitalized as Drilling and Other Property and Equipment, during the periods presented.

No definition available.

+ Details

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- Definition

Most recent ownership percentage of majority stockholder of the Company.

+ References

No definition available.

+ Details

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- Definition

Amount of the cumulative effect on retained earnings net of related income tax effect.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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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.

+ Details

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General Information - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Oct. 26, 2017
Property, Plant and Equipment [Line Items]
Amount capitalized for asset replacements and betterments	$ 33.7	$ 177.6
Adjustments for New Accounting Principle Adoption [Member]
Property, Plant and Equipment [Line Items]
Reduction in retained earnings	$ 0.6
Subsequent Event [Member]
Property, Plant and Equipment [Line Items]
Outstanding common stock owned by Loews Corporation			53.00%