Current Liabilities - Other Current Liabilities (Details) - USD ($) $ in Millions	Jan. 31, 2016	Jul. 31, 2015
Other Liabilities, Current [Abstract]
Reserve for product returns	$ 50	$ 12
Reserve for rebates	40	12
Current portion of license fee payable	10	10
Current portion of deferred rent	3	8
Interest payable	11	10
Executive deferred compensation plan liabilities	59	63
Other	35	35
Total other current liabilities	$ 208	$ 150