6. Income Taxes (Details - Provision for Income taxes) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2017
Income Tax Disclosure [Abstract]
Federal income taxes at statutory rate	$ (1,120)	$ (6,112)	$ 475
State income taxes	(48)	155	309
Expiration and adjustments of deferred tax assets	2,507	1,840	1,693
Change in valuation allowance	(2,480)	(57,599)	(2,616)
Share-based compensation	1,309	1,584	0
Other, net	(452)	6	139
Tax Cuts and Jobs Act	0	60,126	0
Income tax benefit	$ (284)	$ 0	$ 0

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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