Stock-Based Compensation (Summary of Stock Option Activity) (Details)	6 Months Ended
	Jan. 31, 2019 $ / shares shares
Options Outstanding
Beginning balance (in shares) | shares	6,785,812
Options granted (in shares) | shares	908,925
Options exercised (in shares) | shares	(794,462)
Options canceled (in shares) | shares	(34,772)
Ending balance (in shares) | shares	6,865,503
Weighted Average Exercise Price
Beginning balance (in usd per share) | $ / shares	$ 34.93
Granted (in usd per share) | $ / shares	58.02
Exercised (in usd per share) | $ / shares	24.12
Canceled (in usd per share) | $ / shares	49.81
Ending balance (in usd per share) | $ / shares	$ 39.16