v3.20.1
FAIR VALUE MEASUREMENTS - RECONCILIATION FOR ASSETS AND LIABILITIES MEASURE AT FAIR VALUE USING LEVEL 3 (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Total    
Balance at beginning of period $ 176 $ 193
Purchases 443 338
Sales (627) (570)
Issuances (2)  
Settlements 43 (20)
Transfers into Level 3 215 304
Transfers out of Level 3 (88) (55)
Balance at end of period 342 234
Cost of goods sold    
Total    
Total gains and losses (realized/unrealized) included in cost of goods sold 182 44
Readily Marketable Inventories    
Readily Marketable Inventories    
Balance at beginning of period 231 246
Purchases 678 699
Sales (627) (570)
Issuances 0  
Settlements 0 0
Transfers into Level 3 271 276
Transfers out of Level 3 (98) (55)
Balance at end of period 619 633
Total    
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities 13 6
Readily Marketable Inventories | Cost of goods sold    
Readily Marketable Inventories    
Total gains and losses (realized/unrealized) included in cost of goods sold 164 37
Derivatives, Net    
Derivatives, Net    
Balance at beginning of period (24) (6)
Purchases 1 0
Sales 0 0
Issuances (2)  
Settlements (18) 1
Transfers into Level 3 3 1
Transfers out of Level 3 10 0
Balance at end of period (16) (2)
Total    
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities 73 37
Derivatives, Net | Cost of goods sold    
Derivatives, Net    
Total gains and losses (realized/unrealized) included in cost of goods sold 14 2
Trade Accounts Receivable/ Payable, Net    
Trade Accounts Receivable/ Payable, Net    
Balance at beginning of period (31) (47)
Purchases (236) (361)
Sales 0 0
Issuances 0  
Settlements 61 (21)
Transfers into Level 3 (59) 27
Transfers out of Level 3 0 0
Balance at end of period (261) (397)
Total    
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities 5 5
Trade Accounts Receivable/ Payable, Net | Cost of goods sold    
Trade Accounts Receivable/ Payable, Net    
Total gains and losses (realized/unrealized) included in cost of goods sold $ 4 $ 5