FAIR VALUE MEASUREMENTS (Basis of Fair Value Measurements on a Recurring Basis) (Details) - USD ($) $ in Millions		Sep. 30, 2015		Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Already Posted, Aggregate Fair Value		$ 19		$ 29
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	[1],[2]	0		0
Carrying value of interests held	[1],[3]	0		0
Assets, Fair Value Disclosure	[4]	59		93
Long-term Debt, Fair Value	[1],[5]	0		0
Liabilities, Fair Value Disclosure	[1]	64		117
Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	[1],[6]	0		0
US Treasury and Government [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	[1],[6],[7]	0		0
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	[1],[6]	0		0
Quoted Prices in Active Markets for Identical Items (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		0	[2]	0	[8]
Carrying value of interests held		0	[3]	0	[9]
Commodities, Asset		2	[10]	0	[11]
Foreign currency, Asset		0	[10]	0	[11]
Assets, Fair Value Disclosure		641		692
Long-term Debt, Fair Value		0	[5]	0	[12]
Interest Rate Derivative Liabilities, at Fair Value		0	[10]	0	[11]
Commodities, Liability		5	[10]	9	[11]
Foreign currency, Liability		0	[10]	0	[11]
Liabilities, Fair Value Disclosure		5		9
Quoted Prices in Active Markets for Identical Items (Level 1) [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		639	[6]	692	[13]
Quoted Prices in Active Markets for Identical Items (Level 1) [Member] | US Treasury and Government [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0	[6],[7]	0	[13],[14]
Quoted Prices in Active Markets for Identical Items (Level 1) [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0	[6]	0	[13]
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		4,436	[2]	2,705	[8]
Carrying value of interests held		0	[3]	0	[9]
Commodities, Asset		3	[10]	6	[11]
Foreign currency, Asset		94	[10]	116	[11]
Assets, Fair Value Disclosure		5,830		4,144
Long-term Debt, Fair Value		20,842	[5]	21,450	[12]
Interest Rate Derivative Liabilities, at Fair Value		10	[10]	12	[11]
Commodities, Liability		241	[10]	99	[11]
Foreign currency, Liability		94	[10]	161	[11]
Liabilities, Fair Value Disclosure		21,187		21,722
Significant Other Observable Inputs (Level 2) [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		43	[6]	36	[13]
Significant Other Observable Inputs (Level 2) [Member] | US Treasury and Government [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		578	[6],[7]	584	[13],[14]
Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		676	[6]	697	[13]
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		0	[2]	0	[8]
Carrying value of interests held		1,019	[3]	1,328	[9]
Commodities, Asset		0	[10]	0	[11]
Foreign currency, Asset		0	[10]	0	[11]
Assets, Fair Value Disclosure		1,019		1,328
Long-term Debt, Fair Value		0	[5]	0	[12]
Interest Rate Derivative Liabilities, at Fair Value		0	[10]	0	[11]
Commodities, Liability		0	[10]	0	[11]
Foreign currency, Liability		0	[10]	0	[11]
Liabilities, Fair Value Disclosure		0		0
Significant Unobservable Inputs (Level 3) [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0	[6]	0	[13]
Significant Unobservable Inputs (Level 3) [Member] | US Treasury and Government [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0	[6],[7]	0	[13],[14]
Significant Unobservable Inputs (Level 3) [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0	[6]	0	[13]
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	[1],[10]	0		0
Foreign Currency Contract [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	[1],[10]	(58)		(90)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	[1],[10]	(58)		(90)
Commodity Contract [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	[1],[10]	(1)		(3)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	[1],[10]	(6)		(27)
Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	[2]	4,436		2,705
Carrying value of interests held	[3]	1,019		1,328
Commodities, Asset	[10]	4		3
Foreign currency, Asset	[10]	36		26
Assets, Fair Value Disclosure		7,431		6,071
Long-term Debt, Fair Value	[5]	20,842		21,450
Interest Rate Derivative Liabilities, at Fair Value	[10]	10		12
Commodities, Liability	[10]	240		81
Foreign currency, Liability	[10]	36		71
Liabilities, Fair Value Disclosure		21,128		21,614
Estimate of Fair Value Measurement [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	[6]	682		728
Estimate of Fair Value Measurement [Member] | US Treasury and Government [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	[6],[7]	578		584
Estimate of Fair Value Measurement [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	[6]	$ 676		$ 697

[1] Cash collateral amounts represent the estimated net settlement amount when applying netting and set-off rights included in master netting arrangements between the Company and its counterparties and the payable or receivable for cash collateral held or placed with the same counterparty.

[2] Treasury Bills and money market funds included in "Cash and cash equivalents" in the consolidated balance sheets and held at amortized cost, which approximates fair value.

[3] Included in “Accounts and notes receivable – Other” in the consolidated balance sheets. See Note 11 for additional information on transfers of financial assets.

[4] Cash collateral amounts represent the estimated net settlement amount when applying netting and set-off rights included in master netting arrangements between the Company and its counterparties and the payable or receivable for cash collateral held or placed with the same counterparty.

[5] See Note 8 for information on fair value measurements of long-term debt.

[6] The Company’s investments in equity and debt securities are primarily classified as available-for-sale and are included in “Other investments” in the consolidated balance sheets.

[7] U.S. Treasury obligations, U.S. agency obligations, agency mortgage-backed securities and other municipalities’ obligations.

[8] Treasury Bills and money market funds included in "Cash and cash equivalents" in the consolidated balance sheets and held at amortized cost, which approximates fair value.

[9] Included in “Accounts and notes receivable – Other” in the consolidated balance sheets. See Note 11 for additional information on transfers of financial assets.

[10] See Note 8 for the classification of derivatives in the consolidated balance sheets.

[11] See Note 8 for the classification of derivatives in the consolidated balance sheets.

[12] See Note 8 for information on fair value measurements of long-term debt.

[13] The Company’s investments in equity and debt securities are primarily classified as available-for-sale and are included in “Other investments” in the consolidated balance sheets.

[14] U.S. Treasury obligations, U.S. agency obligations, agency mortgage-backed securities and other municipalities’ obligations.