Revenue Recognition - Additional Information (Detail) (USD $)	3 Months Ended
Mar. 31, 2015 Contract Project	Mar. 31, 2014 Project Contract
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Unapproved change orders	$ 240,300,000us-gaap_UnapprovedChangeOrdersAmount	$ 223,500,000us-gaap_UnapprovedChangeOrdersAmount
Revenues	550,463,000us-gaap_Revenues	603,811,000us-gaap_Revenues
Cost of operations	475,459,000us-gaap_CostOfRevenue	591,493,000us-gaap_CostOfRevenue
Number of projects accounted under deferred profit recognition policy	0mdr_NumberOfProjectsInLossPosition	0mdr_NumberOfProjectsInLossPosition
Number of contracts	0mdr_NumberOfContracts	0mdr_NumberOfContracts
MEA [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues	153,800,000	260,300,000
MEA [Member] \| Unconsolidated Joint Ventures [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues	0	0
Cost of operations	0	0
AEA [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues	143,313,000	181,686,000
Consolidated Entities [Member] \| MEA [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues	0	0
Cost of operations	0	0
Claims Revenue \| MEA [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues	6,500,000	6,500,000
Cost of operations	6,500,000	6,500,000
Backlog [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Unapproved change orders	73,000,000	38,100,000
Backlog [Member] \| MEA [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Loss on contracts	166,500,000
Project completion year	2017
Backlog [Member] \| AEA [Member] \| Mexico [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Loss on contracts	130,400,000
Backlog Related to Active Projects [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Loss on contracts	406,700,000
Backlog Associated with Charter Project [Member] \| AEA [Member] \| Brazil [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Loss on contracts	20,800,000
Backlog Associated with Charter of Agile [Member] \| AEA [Member] \| Brazil [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Loss on contracts	$ 87,500,000
Project completion year	2017
Active Projects [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Number of projects accounted under deferred profit recognition policy	4

Number of contracts.

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- Definition

Number of projects in loss position.

+ References

No definition available.

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- Definition

Project completion year.

+ References

No definition available.

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- Definition

The aggregate cost of goods produced and sold and services rendered during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 2

-Article 5

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- Definition

Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Definition

The amount of costs incurred on unapproved change orders when it is probable that the cost will be recovered through a change in the contract price.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c(3)

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 910

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6471523&loc=d3e50000-109363

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 910

-SubTopic 310

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49324-109356

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