Stockholders' Equity Restricted Stock Unit Activity and Related Share-Based Compensation Expense (Details) shares in Thousands	9 Months Ended
	Apr. 30, 2017 $ / shares shares
Number of Shares
Nonvested at beginning of period (in shares) | shares	9,039
Granted, Number of shares (in shares) | shares	819
Vested, Number of Shares (in shares) | shares	(1,333)
Forfeited, Number of Shares (in shares) | shares	(1,167)
Nonvested at end of period (in shares) | shares	7,358
Weighted Average Grant Date Fair Value
Nonvested, Weighted Average Grant Date Fair Value, at beginning of period (in USD per shares) | $ / shares	$ 82.30
Granted, Weighted Average Grant Date Fair Value (in USD per shares) | $ / shares	113.78
Vested, Weighted Average Grant Date Fair Value (in USD per shares) | $ / shares	65.82
Forfeited, Weighted Average Grant Date Fair Value (in USD per shares) | $ / shares	74.41
Nonvested, Weighted Average Grant Date Fair Value, at end of period (in USD per shares) | $ / shares	$ 90.04