Derivatives and Other Financial Instruments - Schedule of Detail for Level 1, 2 and 3 Derivatives (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets Current	$ 24		$ 24		$ 59
Derivative Liabilities Current	47		47		67
Derivative Assets Noncurrent	5		5		18
Derivative Liabilities Noncurrent	203		203		581
Unrealized (loss) gain recognized in Other comprehensive (loss) income	(513)	$ 80	339	$ (272)
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	(13)	(10)	(38)	(1)
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	1	(5)	15	(32)
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	2	(7)	(1)	(25)
Level 1 and 2 Derivative Instruments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets	20		20		3
Derivative Liabilities	44		44		33
Unrealized (loss) gain recognized in Other comprehensive (loss) income	22	5	(7)	(3)
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	(1)	(8)	(15)	(12)
Level 3 Derivative Instruments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets	9		9		74
Derivative Liabilities	206		206		615
Unrealized (loss) gain recognized in Other comprehensive (loss) income	(536)	80	331	(237)
Realized (loss) gain reclassed from Other comprehensive (loss) income to earnings	(14)	$ 5	(22)	$ 36
Level 1, 2 and 3 Derivative Instruments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative Assets	29		29		77
Derivative Liabilities	250		250		648
Derivative Assets Current	24		24		59
Derivative Liabilities Current	47		47		67
Derivative Assets Noncurrent	5		5		18
Derivative Liabilities Noncurrent	$ 203		$ 203		$ 581

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 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, expected to be settled within one year or normal operating cycle, if longer. Includes assets 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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