Accounts Receivable, Unbilled Services and Deferred Revenue - Summary of Accounts Receivable and Unbilled Services (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Apr. 30, 2019
Receivables [Abstract]
Accounts receivable	$ 1,972	$ 1,982
Unbilled services	1,947	2,417
Total accounts receivable and unbilled services	3,919	4,399
Less allowance for doubtful accounts	(28)	(22)
Total accounts receivable, net	$ 3,891	$ 4,377

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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