Related Party Transactions (Details) - Straight Path [Member] - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016
Estimated liability to straight path included in other current liabilities
Balance at beginning of year	$ 133	$ 286
Additional liability	104	59
Adjustments	(51)	(136)
Payments	(105)	(76)
Balance at end of year	$ 81	$ 133