Intangibles, net (Details) - USD ($)	12 Months Ended
Apr. 30, 2021	Apr. 30, 2020	Apr. 30, 2019
Intangibles, net
Amortization expense	$ 6,469,000	$ 2,822,000	$ 357,000
Weighted average
Intangibles, net
Weighted average amortization period	5 years	4 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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