Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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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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The aggregate cost of goods produced and sold and services rendered during the reporting period.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail)		3 Months Ended		6 Months Ended
	May 09, 2018	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	May 08, 2018 USD ($)
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cost of operations		$ 1,498,000,000	$ 650,000,000	$ 1,974,000,000	$ 1,079,000,000
Selling, general and administrative expenses		75,000,000	50,000,000	124,000,000	87,000,000
Loss from investments in unconsolidated affiliates			(1,000,000)		(2,000,000)
Reverse stock split	three-to-one
Reverse stock split, conversion ratio	3
Restructuring and integration costs		63,000,000		75,000,000
Senior secured long-term borrowing						$ 2,260,000,000
Provision for income tax benefit at statutory income tax rate		117,000,000		117,000,000
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Interest rate derivatives						$ 1,940,000,000
Post-Combination Bid and Proposal Expenses [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cost of operations		$ 17,000,000
Pre-Combination Bid and Proposal Expenses [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Selling, general and administrative expenses			9,000,000	10,000,000	16,000,000
Restructuring and Integration Costs [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Restructuring and integration costs				11,000,000
Transaction Costs [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Transaction costs				$ 3,000,000
Oil and Gas and Qingdao McDermott Wuchuan Offshore Engineering Company Ltd [Member] \| Operating Income [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Loss from investments in unconsolidated affiliates			$ 3,000,000		$ 6,000,000