Stockholders' Equity (Details) (USD $)	3 Months Ended														1 Months Ended
	Oct. 31, 2014		Oct. 31, 2013	Oct. 31, 2014 Stock Options [Member]	Oct. 31, 2014 Restricted Stock Units (RSUs) [Member]	Oct. 31, 2014 Cost of revenue [Member]	Oct. 31, 2013 Cost of revenue [Member]	Oct. 31, 2014 Selling and marketing [Member]	Oct. 31, 2013 Selling and marketing [Member]	Oct. 31, 2014 Research and development [Member]	Oct. 31, 2013 Research and development [Member]	Oct. 31, 2014 General and administrative [Member]	Oct. 31, 2013 General and administrative [Member]	Oct. 31, 2014 New Program [Member]	Nov. 21, 2014 Dividend Declared [Member]
Stockholders' Equity (Textuals)
Common stock repurchased (in shares)	1,300,000		17,600,000
Common stock repurchased, value	$ 114,000,000		$ 1,400,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount														1,800,000,000
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)	$ 0.25
Payments of dividends	74,000,000		55,000,000
Dividends declared per common share (in dollars per share)	$ 0.25		$ 0.19												$ 0.25
Total share-based compensation expense
Allocated Share-based Compensation Expense	61,000,000		47,000,000			2,000,000	2,000,000	18,000,000	15,000,000	20,000,000	14,000,000	21,000,000	16,000,000
Income tax benefit	(19,000,000)		(15,000,000)
Increase in net loss from continuing operations	42,000,000		32,000,000
Increase in net loss per share:
Basic (dollars per share)	$ 0.15		$ 0.11
Diluted (dollars per share)	$ 0.15		$ 0.11
Share-based awards available for grant
Shares Available for Grant, Beginning Balance (in shares)	24,203,000
Options granted (in shares)	0
Restricted stock units granted (in shares)	(604,000)	[1]
Share-based awards canceled/forfeited/expired (in shares)	1,791,000	[1],[2]
Shares Available for Grant, Ending Balance (in shares)	25,390,000
Pool Shares Reduced For Each Share Granted (in shares)	2.3
Pool Shares Increased For Each Share Forfeited (in shares)	2.3
Summary of stock option activity
Number of shares, Beginning Balance (in shares)	10,938,000
Weighted average exercise price per share, Beginning Balance (in dollars per share)	$ 52.67
Options granted, number of shares (in shares)	0
Options granted, weighted average exercise price per share (in dollars per share)	$ 0.00
Options exercised, number of shares (in shares)	(1,085,000)
Options exercised, weighted average exercise price per share (in dollars per share)	$ 47.78
Options canceled or expired, number of shares (in shares)	(291,000)
Options canceled or expired, weighted average exercise price per share (in dollars per share)	$ 63.73
Number of shares, Ending Balance (in shares)	9,562,000
Weighted average exercise price per share, Ending Balance (in dollars per share)	$ 52.89
Exercisable (in shares)	5,252,000
Exercisable, Weighted average exercise price per share (in dollars per share)	$ 40.48
Summary of restricted stock unit activity
Nonvested at beginning of period (in shares)	9,455,000
Nonvested, Weighted Average Grant Date Fair Value, at beginning of period (in dollars per shares)	$ 62.46
Granted, Number of shares (in shares)	263,000
Granted, Weighted Average Grant Date Fair Value (in dollars per shares)	$ 82.98
Vested, Number of Shares (in shares)	(709,000)
Vested, Weighted Average Grant Date Fair Value (in dollars per shares)	$ 53.93
Forfeited, Number of Shares (in shares)	(718,000)
Forfeited, Weighted Average Grant Date Fair Value (in dollars per shares)	$ 55.31
Nonvested at end of period (in shares)	8,291,000
Nonvested, Weighted Average Grant Date Fair Value, at end of period (in dollars per shares)	$ 64.46
Unrecognized compensation cost related to non-vested share based compensation expense				$ 59,000,000	$ 349,000,000
Expected weighted average vesting period to recognize compensation cost related to share based compensation expense, in years				2 years 3 months 6 days	2 years 2 months 12 days

[1] RSUs granted from the pool of shares available for grant under our 2005 Equity Incentive Plan reduce the pool by 2.3 shares for each share granted. RSUs forfeited and returned to the pool of shares available for grant increase the pool by 2.3 shares for each share forfeited.

[2] Stock options and restricted stock units canceled, expired or forfeited under our 2005 Equity Incentive Plan are returned to the pool of shares available for grant. Stock options and restricted stock units canceled, expired or forfeited under older expired plans are not returned to the pool of shares available for grant.