Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2011

Financial Instruments [Abstract]

Marketable Securities including Strategic Investments

			Gross		Gross
	Fair		Unrealized		Unrealized			Amortized
As of June 30, 2011 (In millions)	Value		Gains		Losses			Cost
Available-for-sale
Corporate debt securities
Current	$	122.3	$	0.2	$	—		$	122.1
Non-current		352.8		1.3		(0.2	)		351.7
Government securities
Current		504.7		0.3		—			504.4
Non-current		590.7		0.8		(0.1	)		590.0
Mortgage and other asset backed securities
Current		2.2		—		—			2.2
Non-current		240.1		0.5		(0.6	)		240.2
Total available-for-sale securities	$	1,812.8	$	3.1	$	(0.9	)	$	1,810.6
Other Investments
Strategic investments, non-current	$	2.0	$	0.5	$	—		$	1.5

			Gross		Gross
	Fair		Unrealized		Unrealized			Amortized
As of December 31, 2010 (In millions)	Value		Gains		Losses			Cost
Available-for-sale
Corporate debt securities
Current	$	93.2	$	0.1	$	—		$	93.1
Non-current		219.8		2.1		(0.5	)		218.2
Government securities
Current		352.8		0.2		—			352.6
Non-current		432.5		0.6		(0.6	)		432.5
Mortgage and other asset backed securities
Current		2.1		—		—			2.1
Non-current		90.8		0.5		(0.2	)		90.5
Total available-for-sale securities	$	1,191.2	$	3.5	$	(1.3	)	$	1,189.0
Other Investments
Strategic investments, non-current	$	44.8	$	17.5	$	—		$	27.3

Summary of financial assets with original maturities of less than 90 days included within cash and cash equivalents

	As of		As of
	June 30,		December 31,
(In millions)	2011		2010
Commercial paper	$	8.0	$	4.0
Repurchase agreements		80.9		26.0
Short-term debt securities		351.7		621.8
Total	$	440.6	$	651.8

Summary of Contractual Maturities: Available-for-Sale Securities

	As of June 30, 2011				As of December 31, 2010
	Estimated		Amortized		Estimated		Amortized
(In millions)	Fair Value		Cost		Fair Value		Cost
Due in one year or less	$	629.2	$	628.7	$	448.1	$	447.8
Due after one year through five years		1,040.9		1,039.0		664.1		662.4
Due after five years		142.7		142.9		79.0		78.8
Total	$	1,812.8	$	1,810.6	$	1,191.2	$	1,189.0

Proceeds from Marketable Securities, excluding Strategic Investments

	For the Three Months					For the Six Months
	Ended June 30,					Ended June 30,
(In millions)	2011			2010		2011			2010
Proceeds from maturities and sales	$	381.8		$	973.2	$	1,169.8		$	2,002.5
Realized gains	$	0.7		$	7.4	$	3.1		$	13.1
Realized losses	$	(0.5	)	$	1.1	$	(1.3	)	$	1.8