Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Consolidated Statements of Operations
Related party revenue	$ 60,864	$ 55,407	$ 29,594
Tax expense	$ (76)	$ 2,444

Amount of tax (expense) benefit on (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a discontinued operation.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration