Joint Venture and Consortium Arrangements - Summarized Balance Sheet Information for Proportionately Consolidated Collaborative Arrangement (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Current assets	$ 3,239	$ 3,033
Total assets	10,029	9,440
Current liabilities	4,618	$ 4,217
Collaborative Arrangement [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Current assets	70
Total assets	70
Current liabilities	$ 69

Organization consolidation and presentation of financial statements.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.

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