The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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)

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

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

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

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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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Segment Reporting - Information about Operations in Different Segments (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues	$ 806,400,000us-gaap_Revenues	$ 414,595,000us-gaap_Revenues	$ 476,083,000us-gaap_Revenues	$ 603,811,000us-gaap_Revenues	$ 517,338,000us-gaap_Revenues	$ 686,856,000us-gaap_Revenues	$ 647,250,000us-gaap_Revenues	$ 807,488,000us-gaap_Revenues	$ 2,300,889,000us-gaap_Revenues	$ 2,658,932,000us-gaap_Revenues	$ 3,641,624,000us-gaap_Revenues
Operating income (loss)	25,949,000us-gaap_OperatingIncomeLoss	(10,711,000)us-gaap_OperatingIncomeLoss	31,525,000us-gaap_OperatingIncomeLoss	(38,209,000)us-gaap_OperatingIncomeLoss	(317,896,000)us-gaap_OperatingIncomeLoss	(49,216,000)us-gaap_OperatingIncomeLoss	(146,321,000)us-gaap_OperatingIncomeLoss	56,688,000us-gaap_OperatingIncomeLoss	8,554,000us-gaap_OperatingIncomeLoss	(456,745,000)us-gaap_OperatingIncomeLoss	307,139,000us-gaap_OperatingIncomeLoss
Capital expenditures									321,187,000	283,962,000	286,310,000
Depreciation and amortization									93,185,000us-gaap_DepreciationAndAmortization	84,580,000us-gaap_DepreciationAndAmortization	86,440,000us-gaap_DepreciationAndAmortization
Drydock amortization									19,719,000us-gaap_AdjustmentForAmortization	18,467,000us-gaap_AdjustmentForAmortization	25,545,000us-gaap_AdjustmentForAmortization
Asia [Member]
Segment Reporting Information [Line Items]
Revenues									937,615,000	953,838,000	1,575,682,000
Operating income (loss)									55,412,000	(72,159,000)	236,874,000
Capital expenditures									154,735,000	117,060,000	219,920,000
Depreciation and amortization									19,020,000	18,693,000	23,797,000
Drydock amortization									6,255,000	8,917,000	9,487,000
Middle East [Member]
Segment Reporting Information [Line Items]
Revenues									795,666,000	1,167,804,000	1,591,881,000
Operating income (loss)									11,421,000	(169,224,000)	138,733,000
Capital expenditures									99,974,000	127,498,000	29,736,000
Depreciation and amortization									31,876,000	31,699,000	31,119,000
Drydock amortization									2,011,000	2,133,000	2,489,000
Americas, Europe and Africa [Member]
Segment Reporting Information [Line Items]
Revenues									567,608,000	537,290,000	474,061,000
Operating income (loss)									(49,337,000)	(215,362,000)	(68,468,000)
Capital expenditures									53,431,000	22,177,000	32,699,000
Depreciation and amortization									34,494,000	26,788,000	24,589,000
Drydock amortization									11,453,000	7,417,000	13,569,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating income (loss)									(8,942,000)
Capital expenditures									13,047,000	17,227,000	3,955,000
Depreciation and amortization									$ 7,795,000	$ 7,400,000	$ 6,935,000