Joint Venture and Consortium Arrangements - Summarized Balance Sheet Information for Proportionately Consolidated Collaborative Arrangement (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Current assets	$ 6,241	$ 3,555
Total assets	8,300	8,737
Current liabilities	5,885	9,444
Collaborative Arrangement [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Current assets	220	180
Non-current assets	7
Total assets	227	180
Current liabilities	$ 219	$ 175