Accounts Receivable, Unbilled Services and Deferred Revenue - Summary of Accounts Receivable and Unbilled Services (Details) - USD ($) $ in Thousands	Jan. 31, 2019	Apr. 30, 2018
Receivables [Abstract]
Accounts receivable	$ 2,367	$ 1,827
Unbilled services	1,565	2,103
Total accounts receivable and unbilled services	3,932	3,930
Less allowance for doubtful accounts	(13)	(13)
Total accounts receivable, net	$ 3,919	$ 3,917

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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No definition available.

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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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