Revenue Recognition - Summary of Contract Balances (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Apr. 30, 2019
Contract Balances:
Contract assets, current	$ 3,030	$ 1,475
Total contract assets	3,030	1,475
Deferred revenue, current	32,704	33,283
Total deferred revenue	$ 32,704	$ 33,283

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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

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