FINANCIAL INSTRUMENTS (Investments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financial Instruments [Line Items]
Investing Results, Proceeds from sales of available-for-sale securities	$ 114	$ 208
Investing Results, Gross realized gains	23	46
Investing Results, Gross realized losses	(1)	(1)
Contractual Maturities of Debt Securities, Within one year, Amortized Cost	17
Contractual Maturities of Debt Securities, One to five years, Amortized Cost	468
Contractual Maturities of Debt Securities, Six to ten years, Amortized Cost	511
Contractual Maturities of Debt Securities, After ten years, Amortized Cost	198
Contractual Maturities of Debt Securities, Total, Amortized Cost	1,194
Contractual Maturities of Debt Securities, Within one year, Fair Value	17
Contractual Maturities of Debt Securities, One to five years, Fair Value	491
Contractual Maturities of Debt Securities, Six to ten years, Fair Value	542
Contractual Maturities of Debt Securities, After ten years, Fair Value	228
Contractual Maturities of Debt Securities, Total, Fair Value	1,278
Held-to-maturity securities	2,102		1,050
Investments in money market funds	1,369us-gaap_MoneyMarketFundsAtCarryingValue		1,655us-gaap_MoneyMarketFundsAtCarryingValue
Cost method investments, aggregate cost	190us-gaap_CostMethodInvestments		181us-gaap_CostMethodInvestments
Cost method investments, reduction in cost basis due to impairment	$ 0	$ 5

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.