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Related Party Transactions (Details) - Straight Path [Member] - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017
Estimated liability to straight path included in other current liabilities
Balance at beginning of year	$ 81	$ 133
Additional liability		104
Adjustments	(46)	(51)
Payments	(35)	(105)
Balance at end of year		$ 81

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- Definition

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