2. Summary of Significant Accounting Policies (Details Narrative) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Apr. 30, 2020	Apr. 30, 2019
Accounting Policies [Abstract]
Revenue recognized for which the contract liability was recorded in the prior year	$ 16,400	$ 6,200
Depreciation and amortization	830	726
Impairment of long-lived assets	0	0
Restricted cash	$ 350	$ 1,150	$ 350	$ 1,150

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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-Publisher FASB
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-Topic 606
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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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