CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES (TABLES)

3 Months Ended

Mar. 31, 2012

Cash, Cash Equivalents, and Short-term Investments [Abstract]

Schedule of Cash, Cash Equivalents and Short-term Investments [Table Text Block]

Components for cash, cash equivalents and marketable securities (in millions):

March 31, 2012	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Cash	$	14.7	$	—	$	—		$	14.7
Commercial paper, money market funds and other securities	33.5		—		—			33.5
Cash and cash equivalents	48.2		—		—			48.2
U.S. government and agency securities	345.4		2.7		(0.3		)	347.8
Foreign government bonds	22.3		0.6		—			22.9
Asset-back securities	84.0		0.4		—			84.4
Mortgage-back securities	113.6		1.2		(0.1		)	114.7
Corporate notes and bonds	500.9		7.8		(0.5		)	508.2
Municipal securities	14.9		0.1		—			15.0
Marketable securities	1,081.1		12.8		(0.9		)	1,093.0
Total	$	1,129.3	$	12.8	$	(0.9	)	$	1,141.2

December 31, 2011	Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Cash	$	62.1	$	—	$	—		$	62.1
Money market funds	40.1		—		—			40.1
Cash and cash equivalents	102.2		—		—			102.2
U.S. government and agency securities	292.5		3.4		—			295.9
Foreign government bonds	24.9		0.5		—			25.4
Asset-back securities	58.2		0.1		(0.3		)	58.0
Mortgage-back securities	124.1		1.1		(0.3		)	124.9
Corporate notes and bonds	518.0		7.0		(2.4		)	522.6
Municipal securities	11.8		0.1		—			11.9
Marketable securities	1,029.5		12.2		(3.0		)	1,038.7
Total	$	1,131.7	$	12.2	$	(3.0	)	$	1,140.9

Schedule of Realized Gain (Loss) [Table Text Block]

Activity for marketable securities (in millions):  

	Three Months Ended March 31,
	2012		2011
Proceeds from sales and maturities	$	188.1	$	314.0
Gross realized gains	1.6		1.9
Gross realized losses	0.3		1.3
Other-than-temporary impairments on investments	0.3		—

Schedule of Unrealized Loss on Investments [Table Text Block]

Investments with continuous unrealized losses (in millions):

	Less than 12 months					Greater than 12 months
March 31, 2012	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Total Fair Value		Total Unrealized Losses
U.S. government and agency securities	$	95.6	$	(0.3	)	$	—	$	—	$	95.6	$	(0.3	)
Mortgage-backed obligations	21.4		(0.1		)	—		—		21.4		(0.1		)
Corporate notes and bonds	86.0		(0.5		)	—		—		86.0		(0.5		)
Total	$	203.0	$	(0.9	)	$	—	$	—	$	203.0	$	(0.9	)

	Less than 12 months					Greater than 12 months
December 31, 2011	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Total Fair Value		Total Unrealized Losses
Asset-backed obligations	$	31.7	$	(0.1	)	$	1.1	$	(0.2	)	$	32.8	$	(0.3	)
Mortgage-backed obligations	35.1		(0.2		)	1.9		(0.1		)	37.0		(0.3		)
Corporate notes and bonds	137.4		(2.4		)	1.0		—			138.4		(2.4		)
Total	$	204.2	$	(2.7	)	$	4.0	$	(0.3	)	$	208.2	$	(3.0	)