This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of gain (loss) on sale or disposal of assets utilized in financial service operations.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Business segments (Income Statement by Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013 segments	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Number of operating segments (in segments)									2
Revenue	$ 393,733	$ 390,192	$ 367,887	$ 372,999	$ 330,165	$ 347,767	$ 373,512	$ 363,489	$ 1,524,811	$ 1,414,933	$ 1,128,131
Operating income	57,265	55,938	47,138	49,213	37,925	62,904	69,838	70,213	209,554	240,880	160,613
Intangible asset impairment									0	1,161	0
Contingent consideration expense (benefit)									0	(4,568)	12,100
Transaction expenses									2,700	1,751	3,608
(Gain)/loss on sale of assets									614	(1,435)	(634)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income									212,868	237,789	175,687
Depreciation and amortization									60,579	51,804	40,775
Capital expenditures									60,263	49,685	41,163
Operating Segments [Member] \| Drilling & Subsea [Member]
Segment Reporting Information [Line Items]
Revenue									940,807	826,500	659,430
Operating income									155,828	161,160	117,927
Depreciation and amortization									43,971	37,737	30,853
Capital expenditures									40,991	31,118	22,774
Operating Segments [Member] \| Production & Infrastructure [Member]
Segment Reporting Information [Line Items]
Revenue									585,495	589,204	468,701
Operating income									86,471	97,257	77,997
Depreciation and amortization									13,952	13,163	9,845
Capital expenditures									10,940	13,644	13,621
Operating Segments [Member] \| Corporate [Member]
Segment Reporting Information [Line Items]
Operating income									(29,431)	(20,628)	(20,237)
Depreciation and amortization									2,656	904	77
Capital expenditures									8,332	4,923	4,768
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue									$ (1,491)	$ (771)	$ 0