Asset impairment charges net of tax and noncontrolling interest.

No definition available.

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- Definition

Gain loss on disposition of assets net of tax and noncontrolling interests.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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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
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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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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Property, Plant and Equipment - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	May 31, 2017 USD ($)	Sep. 30, 2017 Rig	Jun. 30, 2017 USD ($) Rig	Sep. 30, 2016 USD ($)
Diamond Offshore [Member]
Property, Plant and Equipment [Line Items]
Asset impairment charge, before tax and noncontrolling interests			$ 72	$ 672
Asset impairment charge, net of tax and noncontrolling interests			$ 23	$ 263
Diamond Offshore [Member] \| Drilling Rigs [Member]
Property, Plant and Equipment [Line Items]
Number of rigs evaluated for impairment \| Rig		6	7
Diamond Offshore [Member] \| Ultra Deepwater [Member]
Property, Plant and Equipment [Line Items]
Number of rigs impaired \| Rig			1
Diamond Offshore [Member] \| Deepwater Semisubmersible Rigs [Member]
Property, Plant and Equipment [Line Items]
Number of rigs impaired \| Rig			1
Boardwalk Pipeline [Member]
Property, Plant and Equipment [Line Items]
Proceed from sale of plant and equipment	$ 64
Gain (loss) on sale of plant and equipment	(47)
Gain (loss) on sale of plant and equipment,net of tax and noncontrolling interests	$ (15)