Derivatives and Other Financial Instruments - Schedule of Reconciliation of Activity for Derivative Contracts (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Financial Contracts [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets, Beginning balance	$ 16	$ 52
Other income, net (unrealized/realized)		0
Settlements and other	(53)	(11)
Fair value measurement, Assets, Ending balance	24	$ 16
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]		Costs And Operating Expenses And Nonoperating Income Expenses
Financial Contracts [Member] | Sales [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets		$ 0
Financial Contracts [Member] | Cost of Goods Sold [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets		(20)
Financial Contracts [Member] | Other Expenses, Net [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets	61	(5)
Financial Contracts [Member] | Other Income Net [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets	61	(5)
Power Contract [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets, Beginning balance	0	0
Other income, net (unrealized/realized)		4
Settlements and other	0	0
Fair value measurement, Assets, Ending balance		0
Fair value measurement, Liabilities, Beginning balance	1,297	1,212
Fair value measurement, Liabilities	$ 0	$ (245)
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	Sales (E)	Sales (E)
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Sales (E)
Other comprehensive (income) loss (unrealized)	$ 70	$ 330
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]	Net change in unrecognized gains/losses on cash flow hedges	Net change in unrecognized gains/losses on cash flow hedges
Fair value measurement, Liabilities, Ending balance	$ 1,077	$ 1,297
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]		Costs And Operating Expenses And Nonoperating Income Expenses
Power Contract [Member] | Sales [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets		$ (4)
Fair value measurement, Liabilities	(290)
Power Contract [Member] | Cost of Goods Sold [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets		0
Power Contract [Member] | Other Expenses, Net [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets		0
Fair value measurement, Liabilities	0
Power Contract [Member] | Other Income Net [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Assets		0
Embedded Credit Derivative [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Settlements and other	(1)
Fair value measurement, Liabilities, Beginning balance	0
Fair value measurement, Liabilities	$ 3
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	Sales (E)
Other comprehensive (income) loss (unrealized)	$ 0
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]	Net change in unrecognized gains/losses on cash flow hedges
Fair value measurement, Liabilities, Ending balance	$ 2	$ 0
Embedded Credit Derivative [Member] | Sales [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Liabilities	0
Embedded Credit Derivative [Member] | Other Expenses, Net [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value measurement, Liabilities	$ 3