v3.26.3
Derivatives (Classification of Gross Fair Values of Derivative Instruments, Excluding Cash Collateral) (Detail) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Commodity derivatives | Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent    
Derivative [Line Items]    
Asset $ 2,062 $ 243
Liability 2,193 236
Commodity derivatives | Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent    
Derivative [Line Items]    
Asset 146 0
Liability 109 0
Embedded derivatives in commodity contracts | Balance Sheet Location [Axis]: us-gaap:DeferredCreditsAndOtherLiabilitiesNoncurrent    
Derivative [Line Items]    
Asset [1] 0 0
Liability [1] 1,399 35
Embedded derivatives in commodity contracts | Balance Sheet Location [Axis]: us-gaap:OtherLiabilitiesCurrent    
Derivative [Line Items]    
Asset [1] 0 0
Liability [1],[2] $ 604 $ 6
[1] Includes embedded derivatives and SPR liability.
[2] See Note 16 for derivative liabilities included within Other current liabilities.