Restructuring - Roll Forward of Accrued Liabilities Associated with Restructuring Activities (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2015 USD ($)
Restructuring Reserve [Line Items]
Beginning balance	$ 4,048
Accruals	6,636
Payments/ Reversals	(4,366)
Ending balance	6,318
Morgan City environmental reserve [Member]
Restructuring Reserve [Line Items]
Beginning balance	3,675
Payments/ Reversals	(2,101)
Ending balance	1,574
Morgan City yard-related expenses and Other [Member]
Restructuring Reserve [Line Items]
Beginning balance	373
Accruals	343
Payments/ Reversals	(453)
Ending balance	263
MPI related accruals [Member]
Restructuring Reserve [Line Items]
Accruals	6,293
Payments/ Reversals	(1,812)
Ending balance	$ 4,481

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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=56944662&loc=d3e3602-108585

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

+ Details

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Balance Type:	credit
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- Definition

Amount of (expense) reversal of expense related to a previously accrued restructuring cost liability. Excludes adjustments for costs incurred, costs settled, and foreign currency translation adjustments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 40

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6394291&loc=d3e17658-110867

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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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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