13. Income Taxes (Details) - Schedule of Unrecognized Tax Benefits Roll Forward - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2019	Apr. 30, 2018
Schedule of Unrecognized Tax Benefits Roll Forward [Abstract]
Balance at the beginning of the fiscal year	$ 1,264	$ 1,626
Additions based on positions taken in the current year	0	0
Additions based on positions taken in prior years	142	0
Decreases based on positions taken in prior years	(119)	(304)
Lapse in statute of limitations	(29)	(58)
Balance at the end of the fiscal year	$ 1,258	$ 1,264

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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