Business Combination - Schedule of Purchase Consideration (Detail) $ / shares in Units, $ in Millions	May 10, 2018 USD ($) $ / shares shares
Business Acquisition [Line Items]
Total Combination consideration transferred, net of cash acquired	$ 4,100
Chicago Bridge & Iron Company N.V. [Member]
Business Acquisition [Line Items]
CB&I shares for Combination consideration \| shares	103
Business combination, number of McDermott's shares entitled for each share of CB&I owned \| shares	85
McDermott stock price on May 10, 2018 \| $ / shares	$ 19.92
Equity Combination consideration transferred	$ 1,684
Fair value of converted awards earned prior to the Combination	9
Total equity Combination consideration transferred	1,693
Cash consideration transferred	2,872
Total Combination consideration transferred	4,565
Less: Cash acquired	(498)
Total Combination consideration transferred, net of cash acquired	$ 4,067

Business combination Cash consideration transferred.

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Business combination consideration transferred for equity.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Fair value at acquisition-date of the assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interests issued by the acquirer, including but not limited to, instruments or interests issued or issuable in consideration for the business combination.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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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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