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Percentage of ownership interest in subsidiary acquired by third party.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

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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.

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

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Stockholders' Equity and Equity-Based Incentive Plans - Additional Information (Detail) shares in Millions, $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended
	May 10, 2018 USD ($) shares	Jan. 31, 2019 USD ($) Installment	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2002 USD ($)
Accumulated Other Comprehensive Income Loss [Line Items]
Stock-based compensation expense			$ 2	$ 4
P.T. Sarana Interfab Mandiri [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Percentage of participating interest acquired in subsidiary					25.00%
Option to sell interest					$ 5
SG&A [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Stock-based compensation expense			6	$ 3
Chicago Bridge & Iron Company N.V. [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Business combination, number of McDermott's shares entitled for each share of CB&I owned \| shares	84.5
Business combination, Consideration	$ 2,870
Payment during period	$ 4,565
Chicago Bridge & Iron Company N.V. [Member] \| Restricted Stock Units [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Stock-settled equity-based awards, restricted stock units, unvested \| shares	2.1
Chicago Bridge & Iron Company N.V. [Member] \| Restricted Stock Units [Member] \| Minimum [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Stock-settled equity-based awards, restricted stock units, vesting period	3 years
Chicago Bridge & Iron Company N.V. [Member] \| Restricted Stock Units [Member] \| Maximum [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Stock-settled equity-based awards, restricted stock units, vesting period	4 years
Chicago Bridge & Iron Company N.V. [Member] \| Stock Options [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Stock-settled equity-based awards, stock options, unvested \| shares	0.1
PT McDermott Indonesia [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Business combination, Consideration		$ 29
Number of installments payable \| Installment		3
Payment during period			5
Remaining liability			$ 24