CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Cash and Cash Equivalents [Abstract]
Cash	$ 5us-gaap_Cash		$ 4us-gaap_Cash
Money market funds and other securities	46us-gaap_MoneyMarketFundsAtCarryingValue		103us-gaap_MoneyMarketFundsAtCarryingValue
Cash and cash equivalents	51	90	107	80
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	1,254		1,110
Marketable securities, Unrealized Gains		8	3
Marketable securities, Unrealized Losses		(1)	(3)
Marketable securities, Fair Value	1,261		1,110
Cash and marketables securities, Cost Basis	1,305		1,217
Cash and marketable securities, Unrealized Gains		8	3
Cash and marketable securities, Unrealized Losses		(1)	(3)
Total cash and marketable securities	1,312		1,217
Available-for-sale Securities, Activity [Abstract]
Proceeds from sales and maturities	259	227
Gross realized gains	1	1
Gross realized losses	(1)	(1)
U.S. government and agency securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	200		166
Marketable securities, Unrealized Gains		1	0
Marketable securities, Unrealized Losses		0	0
Marketable securities, Fair Value	201		166
Foreign government bonds [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	31		25
Marketable securities, Unrealized Gains		0	0
Marketable securities, Unrealized Losses		0	0
Marketable securities, Fair Value	31		25
Asset-backed securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	151		130
Marketable securities, Unrealized Gains		0	0
Marketable securities, Unrealized Losses		0	0
Marketable securities, Fair Value	151		130
Mortgage-backed securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	127		127
Marketable securities, Unrealized Gains		1	0
Marketable securities, Unrealized Losses		(1)	(1)
Marketable securities, Fair Value	127		126
Corporate notes and bonds [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	721		644
Marketable securities, Unrealized Gains		6	3
Marketable securities, Unrealized Losses		0	(2)
Marketable securities, Fair Value	727		645
Municipal securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	24		18
Marketable securities, Unrealized Gains		0	0
Marketable securities, Unrealized Losses		0	0
Marketable securities, Fair Value	$ 24		$ 18

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Cash and Available for Sale Securities Accumulated Gross Unrealized Gain Before Tax

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- Definition

Cash and Available for Sale Securities Accumulated Gross Unrealized Loss Before Tax

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- Definition

Total Cash And Marketable Securities, Amortized Cost Basis

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB

-Name Accounting Standards Codification

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This item represents the cost of debt and equity 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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.2)

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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-Subparagraph (b)

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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-Name Accounting Standards Codification

-Glossary Cash

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-Glossary Cash Equivalents

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-Name Regulation S-X (SX)

-Number 210

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-Article 5

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-Subparagraph (SX 210.5-02.1)

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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