XML 50 R38.htm IDEA: XBRL DOCUMENT v3.20.2
Fair Value Measurements (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Aug. 26, 2020
Dec. 31, 2019
Fair Value Measurements [Line Items]            
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) $ (635) $ (81) $ (1,100) $ (258)    
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss) $ 392 $ 165 $ 1,200 $ 656    
Weighted Average [Member] | Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Inventory Related Payables [Member]            
Fair Value Measurements [Line Items]            
Basis 56.40%   56.40%     14.70%
Weighted Average [Member] | Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Inventories Carried At Market [Member]            
Fair Value Measurements [Line Items]            
Basis 20.60%   20.60%     28.20%
Bonds Zero Percent Due in 2023 [Member]            
Fair Value Measurements [Line Items]            
Debt Instrument, Face Amount         $ 300