Property, Plant and Equipment - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015 Rigs
Property, Plant and Equipment [Line Items]
Asset impairment loss, before tax and noncontrolling interests	$ 359
Number of rigs expects to retire and scrap	3l_NumberOfRigsRetireAndScrapped
Aggregate fair value of impaired rigs	14
Diamond Offshore [Member]
Property, Plant and Equipment [Line Items]
Asset impairment loss, before tax and noncontrolling interests	359
Asset impairment loss, net of tax and noncontrolling interests	158
Number of rigs currently cold stacked	5
Number of rigs currently under contract	3
Drillship [Member] \| Diamond Offshore [Member]
Property, Plant and Equipment [Line Items]
Number of equipment evaluated for impairment	1
Mid-Water Semisubmersible Rigs [Member] \| Diamond Offshore [Member]
Property, Plant and Equipment [Line Items]
Number of equipments impaired	7
Number of rigs expects to retire and scrap	3
Loews Hotels [Member]
Property, Plant and Equipment [Line Items]
Amount paid for acquisition	$ 330

Number of property plant and equipment for impairment.

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Number of property plant and equipment impaired.

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Number of rigs cold stacked.

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Number of rigs retire and scrapped.

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Number of working rigs

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Other asset impairment charges net of tax and noncontrolling interest.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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-Glossary Impairment

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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