v2.4.0.6

Stockholders' Equity (Tables)

9 Months Ended

Jan. 27, 2012

Stockholders' Equity [Abstract]

Combined Activity Under Stock Option Plans And Agreements

		Number of  Shares				Weighted- Average Exercise Price				Weighted- Average Remaining Contractual Term (Years)				Aggregate Intrinsic Value
	Outstanding at April 29, 2011												24.5						$	26.62
	Options granted												2.1							51.36
	Options exercised												(3.0				)			20.98
	Options forfeitures and cancellations												(0.7				)			35.96
Outstanding at January 27, 2012			22.9				29.28				3.91			$	239.6
Options vested and expected to vest as of January 27, 2012			22.1				28.86				3.86				236.7
Exercisable at January 27, 2012			15.1				25.64				3.25				188.9

Additional Information Related To Stock Options

		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Weighted-average fair value per share granted		$	13.26			$	18.79			$	16.88			$	15.72
Weighted-average fair value per share of options assumed in acquisition			N/A				N/A				N/A			$	21.15
Intrinsic value of options exercised		$	21.0			$	79.4			$	71.6			$	294.0
Proceeds received from the exercise of stock options		$	19.5			$	53.9			$	62.2			$	278.8
Fair value of options vested		$	18.1			$	23.1			$	56.8			$	77.5

Activity Related To Restricted Stock Units (RSUs)

		Number of Shares				Weighted- Average Grant Date Fair Value
Outstanding at April 29, 2011			10.1			$	35.79
RSUs granted			5.3				48.84
RSUs vested			(3.1	)			29.92
RSUs forfeitures and cancellations			(0.7	)			39.90
Outstanding at January 27, 2012			11.6				43.10

Number And Value Of The Shares Netted For Employee Taxes

		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Shares withheld for taxes			0.4				0.3				1.0				0.8
Fair value of shares withheld and retired		$	16.4			$	15.9			$	44.2			$	35.5

Schedule Of Employee Stock Purchase Plan (ESPP) Disclosures

		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Weighted-average fair value per right granted		$	12.93			$	16.54			$	13.34			$	15.35
Shares issued under the ESPP			1.5				3.2				2.6				6.0
Weighted-average price per share issued		$	31.03			$	11.87			$	34.53			$	11.50

Stock-Based Compensation Expense

		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Cost of product revenues		$	1.6			$	1.0			$	4.1			$	2.7
Cost of service revenues			5.7				3.6				13.8				10.6
Sales and marketing			37.5				21.3				96.5				59.2
Research and development			22.8				11.3				57.0				31.6
General and administrative			9.1				7.8				26.4				22.9
Total stock-based compensation expense		$	76.7			$	45.0			$	197.8			$	127.0

Stock-Based Compensation Expense Associated With Each Type Of Award

		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Employee stock options		$	13.8			$	13.8			$	43.0			$	39.7
RSUs and restricted stock awards			42.1				23.9				115.4				61.7
ESPP			20.8				7.3				39.4				25.6
Total stock-based compensation expense		$	76.7			$	45.0			$	197.8			$	127.0

Income Tax Benefits Associated With Employee Stock Transactions

		Nine Months Ended
		January 27, 2012				January 28, 2011
Income tax benefits associated with employee stock transactions		$	74.7			$	74.9

Valuation Assumptions

		Stock Options
		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Expected term in years			4.8				4.8				4.8				4.8
Risk-free interest rate			0.84	%			2.07	%			1.54	%			1.99	%
Volatility			43	%			37	%			36	%			37	%

		ESPP
		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Expected term in years			1.2				1.3				1.2				1.2
Risk-free interest rate			0.18	%			0.35	%			0.19	%			0.43	%
Volatility			45	%			39	%			44	%			39	%

Contracts' Value Allocated To Cost Of Shares Repurchased And To The Value Of The ASR Forward Contracts

		Shares of Common Stock				Additional Paid-in Capital				Retained Earnings				Total Repurchase Activity
Repurchase and retirement of common stock			(14.6	)		$	(125.8	)		$	(474.1	)		$	(599.9	)
Value of ASR forward contracts							(0.1	)							(0.1	)
Total cash payment			(14.6	)		$	(125.9	)		$	(474.1	)		$	(600.0	)

Components Of Accumulated Other Comprehensive Income, Net Of Related Immaterial Tax Effects

		January 27, 2012				April 29, 2011
Accumulated translation adjustments		$	4.2			$	11.6
Accumulated unrealized gains on available-for-sale investments			1.5				3.4
Accumulated unrealized gains (losses) on derivatives qualifying as cash flow hedges			1.9				(2.2	)
Accumulated defined benefit obligation adjustments			(3.0	)			0.0
Total accumulated other comprehensive income		$	4.6			$	12.8

Components Of Comprehensive Income, Net Of Related Immaterial Tax Effects

		Three Months Ended								Nine Months Ended
		January 27, 2012				January 28, 2011				January 27, 2012				January 28, 2011
Net income		$	119.6			$	186.4			$	424.7			$	512.5
Change in currency translation adjustments			(4.3	)			0.4				(7.4	)			4.7
Change in unrealized gains (losses) on available-for-sale investments			3.5				(6.4	)			(1.9	)			(0.1	)
Change in unrealized gains (losses) on derivatives qualifying as cash flow hedges			1.4				2.2				4.1				(0.2	)
Change in defined benefit obligation adjustments			(3.0	)			0.0				(3.0	)			0.0
Comprehensive income		$	117.2			$	182.6			$	416.5			$	516.9

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