Revenue Recognition - Summary of contract liabilities activity (Details) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2018	Jul. 31, 2018
Contract Liabilities
Beginning Balance	$ 29,015
Revenue deferred in current year	14,524
Deferred revenue recognized	(13,547)
Foreign currency translation	(163)
Ending Balance	29,829
Contract liabilities included in Other long-term liabilities	(549)
Deferred revenue	$ 29,280	$ 28,614

Change in Contract with Customer, Liability [Roll Forward]

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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