Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Net number of non-option equity instruments granted to participants.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of non-vested options outstanding.

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Number of share options (or share units) exercised during the current period.

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Equity-Based Compensation - Additional Information (Detail) - USD ($)		1 Months Ended	12 Months Ended
	May 10, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock options, granted			0	0	0
Number of options, exercised				0	0
Outstanding stock options			500,000
Stock options, weighted-average exercise price per share			$ 37
Tax benefits realized related to RSUs and RSAs			$ 0	$ 0	$ 0
RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-settled equity-based awards, RSUs, unvested			3,000,000	2,000,000
Number of units settled in cash			2,000,000
Performance Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted			400,000	200,000	400,000
Number of units settled in cash		500,000
Liability Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs related to awards			$ 3,000,000
Expected weighted-average period for recognition of compensation cost			2 years
Chicago Bridge & Iron Company N.V. [Member] \| RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-settled equity-based awards, RSUs, unvested	2,100,000
Chicago Bridge & Iron Company N.V. [Member] \| RSUs [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-settled equity-based awards, restricted stock units, vesting period	3 years
Chicago Bridge & Iron Company N.V. [Member] \| RSUs [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-settled equity-based awards, restricted stock units, vesting period	4 years
Chicago Bridge & Iron Company N.V. [Member] \| Stock Options and Stock Appreciation Rights [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-settled equity-based awards, stock options and stock appreciation rights, unvested	100,000
McDermott International, Inc. 2016 Long-Term Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining number of shares available for future awards			5,000,000