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CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011
Cash and Cash Equivalents [Abstract]
Cash	$ 27		$ 28
Money market funds and other securities	68		94
Cash and cash equivalents	95	48	122	102
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	1,161		1,119
Marketable securities, Unrealized Gains	10		12
Marketable securities, Unrealized Losses	(1)		(1)
Marketable securities, Fair Value	1,170		1,130
Cash and marketables securities, Cost Basis	1,256		1,241
Total cash and marketable securities	1,265		1,252
Available-for-sale Securities, Activity [Abstract]
Proceeds from sales and maturities	239	188
Gross realized gains	2	2
Gross realized losses	(1)	(1)
U.S. government and agency securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	290		271
Marketable securities, Unrealized Gains	1		1
Marketable securities, Unrealized Losses	0		0
Marketable securities, Fair Value	291		272
Foreign government bonds [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	33		50
Marketable securities, Unrealized Gains	0		1
Marketable securities, Unrealized Losses	0		0
Marketable securities, Fair Value	33		51
Asset-backed securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	73		61
Marketable securities, Unrealized Gains	1		1
Marketable securities, Unrealized Losses	0		0
Marketable securities, Fair Value	74		62
Mortgage-backed securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	131		137
Marketable securities, Unrealized Gains	1		1
Marketable securities, Unrealized Losses	(1)		(1)
Marketable securities, Fair Value	131		137
Corporate notes and bonds [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	612		577
Marketable securities, Unrealized Gains	7		8
Marketable securities, Unrealized Losses	0		0
Marketable securities, Fair Value	619		585
Municipal securities [Member]
Available-for-sale Securities, Current [Abstract]
Marketable securities, Cost Basis	22		23
Marketable securities, Unrealized Gains	0		0
Marketable securities, Unrealized Losses	0		0
Marketable securities, Fair Value	$ 22		$ 23