Fair Value Measurements - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate carrying value of assets	$ 8,300	$ 8,737
Spoolbase Facilities [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Impairment charges	3
Marine Assets [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate carrying value of assets	1,340
Estimated fair value of assets	463
Impairment charges	$ 881
Marine Assets [Member] \| Future Cash Flows, Discounted Risk-adjusted Rate [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets fair value, measurement input	0.10

Value of input used to measure alternative investment.

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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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