FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - RECONCILIATION FOR ASSETS AND LIABILITIES MEASURE AT FAIR VALUE USING LEVEL 3 (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Balance at beginning of period	$ 142	$ 368
Purchases	437	342
Sales	(372)	(248)
Issuances	(2)
Settlements	17	(66)
Transfers into Level 3	177	135
Transfers out of Level 3	(34)	(7)
Balance at end of period	299	455
Cost of goods sold
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Total gains and losses (realized/unrealized) included in cost of goods sold	(66)	(69)
Changes in unrealized gains and (losses) relating to assets and liabilities	(65)	(102)
Derivatives, Net
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Balance at beginning of period	(51)	167
Purchases	4
Issuances	(2)
Settlements	17	(66)
Transfers into Level 3	(4)
Transfers out of Level 3	23
Balance at end of period	(72)	16
Derivatives, Net \| Cost of goods sold
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Total gains and losses (realized/unrealized) included in cost of goods sold	(59)	(85)
Changes in unrealized gains and (losses) relating to assets and liabilities	(54)	(79)
Readily Marketable Inventories
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Balance at beginning of period	237	245
Purchases	764	537
Sales	(372)	(248)
Transfers into Level 3	184	192
Transfers out of Level 3	(56)	(7)
Balance at end of period	743	730
Readily Marketable Inventories \| Cost of goods sold
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Total gains and losses (realized/unrealized) included in cost of goods sold	(14)	11
Changes in unrealized gains and (losses) relating to assets and liabilities	(13)	(24)
Trade Accounts Receivable/Payable, Net
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Balance at beginning of period	(44)	(44)
Purchases	(331)	(195)
Transfers into Level 3	(3)	(57)
Transfers out of Level 3	(1)
Balance at end of period	(372)	(291)
Trade Accounts Receivable/Payable, Net \| Cost of goods sold
Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)
Total gains and losses (realized/unrealized) included in cost of goods sold	7	5
Changes in unrealized gains and (losses) relating to assets and liabilities	$ 2	$ 1

Amount of purchases of financial instruments measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. The instruments include marketable inventories and derivative asset (liability) after deduction of derivative liability (asset).

No definition available.