Description of Business and Summary of Significant Accounting Policies - Schedule of Composition of Basic and Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Oct. 31, 2019	Oct. 31, 2018
Accounting Policies [Abstract]
Net income	$ 57	$ 34
Shares used in basic per share amounts:
Weighted average common shares outstanding (in shares)	261	260
Shares used in diluted per share amounts:
Weighted average common shares outstanding (in shares)	261	260
Dilutive common equivalent shares from stock options and restricted stock awards (in shares)	3	4
Dilutive weighted average common shares outstanding (in shares)	264	264
Basic and diluted net income per share:
Basic net income per share (in dollars per share)	$ 0.22	$ 0.13
Diluted net income per share (in dollars per share)	$ 0.22	$ 0.13
Shares excluded from diluted net income per share:
Weighted average stock options and restricted stock units that have been excluded from dilutive common equivalent shares outstanding due to their anti-dilutive effect (in shares)	0	0