Adjustments to additional paid in capital common stock payable for prepaid service.

No definition available.

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Namespace Prefix:	mdr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Increase decrease in equity method investment.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.30(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 31
-Article 5

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Balance Type:	credit
Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Balance Type:	na
Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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Balance Type:	na
Period Type:	instant

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Balance Type:	credit
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- Definition

Amount of equity attributable to noncontrolling interests of an equity method investment of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (f)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=51717284&loc=SL51721683-107760

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(g))
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-Name Accounting Standards Codification
-Topic 323
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-Paragraph 2
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph g
-Subparagraph 1, 2
-Article 4

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph w
-Article 1

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph bb
-Article 1

+ Details

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Net Increase or Decrease in balance of noncontrolling interest in the subsidiary during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4568740-111683

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

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- Details

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- Details

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- Details

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- Details

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- Details

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Acquisitions - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($) JointVentures shares	Dec. 31, 2015 USD ($)
Business Acquisition [Line Items]
Increase in capital in excess of par value	$ 240,044
Number of joint ventures entered \| JointVentures		2
Equity method investment recorded	38,186	$ 26,000	$ 26,551
Non controlling interest of equity method investment	21,000	21,000
Capital in excess of par value	3,000	5,000
Decrease in equity method investment	$ 5,000
Oceanteam ASA [Member]
Business Acquisition [Line Items]
Percentage of interest acquired in subsidiary	50.00%
Purchase consideration - cash	$ 33,000
Decrease in noncontrolling interest recorded	(44,000)
Increase in capital in excess of par value	11,000
Deepsea Group Limited [Member]
Business Acquisition [Line Items]
Purchase consideration - cash		6,000
Total purchase consideration		$ 9,000
Deepsea Group Limited [Member] \| Restricted Shares [Member]
Business Acquisition [Line Items]
Purchase consideration - restricted shares \| shares		313,580
THHE Fabricators Sdn. Bhd [Member]
Business Acquisition [Line Items]
Percentage of interest acquired in subsidiary		30.00%
Increase in capital in excess of par value	(2,000)
Equity method investment recorded	$ 21,000
Berlian McDermott Sdn, Bhd, [Member]
Business Acquisition [Line Items]
Percentage of interest acquired in subsidiary		30.00%