13. Income Taxes (Details) - Schedule of Components of Income Tax Expense (Benefit) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2019	Apr. 30, 2018
Schedule of Components of Income Tax Expense (Benefit) [Abstract]
Federal	$ 8	$ (869)
Foreign	196	0
State	99	(124)
Current provision	303	(993)
Federal	0	10,702
Foreign	(247)	267
State	0	1,200
Deferred (benefit) tax	(247)	12,169
Total provision	$ 56	$ 11,176

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