Stock-Based Compensation (Summary of Stock Option Activity) (Details)	3 Months Ended
	Oct. 31, 2019 $ / shares shares
Options Outstanding
Beginning balance (in shares) | shares	6,531,250
Options granted (in shares) | shares	879,541
Options exercised (in shares) | shares	(389,551)
Options canceled (in shares) | shares	(17,996)
Ending balance (in shares) | shares	7,003,244
Weighted Average Exercise Price
Beginning balance (in usd per share) | $ / shares	$ 39.66
Granted (in usd per share) | $ / shares	51.61
Exercised (in usd per share) | $ / shares	28.71
Canceled (in usd per share) | $ / shares	49.98
Ending balance (in usd per share) | $ / shares	$ 41.74