Derivatives and Other Financial Instruments - Schedule of Detail for Level 1, 2 and 3 Derivatives (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets Current	$ 15		$ 21
Derivative Liabilities Current	181		103
Derivative Liabilities Noncurrent	923		742
Unrealized (loss) gain recognized in Other comprehensive (loss) income	(303)	$ 852
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	(52)	(25)
Non-controlling and Equity Interest [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unrealized (loss) gain recognized in Other comprehensive (loss) income	11	14
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	3	(3)
Level 1 and 2 Derivative Instruments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets	15		21
Derivative Liabilities	24		7
Unrealized (loss) gain recognized in Other comprehensive (loss) income	(14)	(29)
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings		(14)
Level 3 Derivative Instruments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Liabilities	1,080		838
Unrealized (loss) gain recognized in Other comprehensive (loss) income	(300)	867
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	(55)	$ (8)
Level 1, 2 and 3 Derivative Instruments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets	15		21
Derivative Liabilities	1,104		845
Derivative Assets Current	15		21
Derivative Liabilities Current	181		103
Derivative Liabilities Noncurrent	$ 923		$ 742

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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