CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Revenue	$ 3,125,745us-gaap_Revenues	$ 2,928,132us-gaap_Revenues
Cost of revenue	2,755,574us-gaap_CostOfServices	2,626,730us-gaap_CostOfServices
Gross profit	370,171us-gaap_GrossProfit	301,402us-gaap_GrossProfit
Selling and administrative expense	109,101	119,167
Intangibles amortization	15,652us-gaap_AmortizationOfIntangibleAssets	16,234us-gaap_AmortizationOfIntangibleAssets
Equity earnings	(4,202)	(4,165)
Other operating expense (income), net	2,822us-gaap_OtherOperatingIncomeExpenseNet	(384)us-gaap_OtherOperatingIncomeExpenseNet
Integration related costs	0	8,067
Income from operations	246,798us-gaap_OperatingIncomeLoss	162,483us-gaap_OperatingIncomeLoss
Interest expense	(22,286)us-gaap_InterestExpense	(18,887)us-gaap_InterestExpense
Interest income	2,048us-gaap_InvestmentIncomeInterest	2,060us-gaap_InvestmentIncomeInterest
Income before taxes	226,560	145,656
Income tax expense	(69,811)us-gaap_IncomeTaxExpenseBenefit	(42,910)us-gaap_IncomeTaxExpenseBenefit
Net income	156,749us-gaap_ProfitLoss	102,746us-gaap_ProfitLoss
Less: Net income attributable to noncontrolling interests	(24,521)	(13,795)
Net income attributable to CB&I	132,228us-gaap_NetIncomeLoss	88,951us-gaap_NetIncomeLoss
Net income attributable to CB&I per share:
Basic (in dollars per share)	$ 1.22us-gaap_EarningsPerShareBasic	$ 0.83us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 1.21us-gaap_EarningsPerShareDiluted	$ 0.82us-gaap_EarningsPerShareDiluted
Weighted average shares outstanding:
Basic (in shares)	108,197	107,677
Diluted (in shares)	109,261	109,113
Cash dividends on shares:
Amount	$ 7,597us-gaap_DividendsCommonStockCash	$ 7,559us-gaap_DividendsCommonStockCash
Per share (in dollars per share)	$ 0.07	$ 0.07

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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

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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).

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