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Schedule of Revenue by Major Customers by Reporting Segments (Details) - Revenue Benchmark [Member] - Customer Concentration Risk [Member]	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021
Transocean Ltd [Member]
Product Information [Line Items]
Revenues, percentage	15.00%
Valaris PLC [Member]
Product Information [Line Items]
Revenues, percentage	12.00%
Diamond Offshore Drilling Inc [Member]
Product Information [Line Items]
Revenues, percentage	11.00%
Department of Energy [Member]
Product Information [Line Items]
Revenues, percentage	11.00%
Enel Green Power Chile LTDA [Member]
Product Information [Line Items]
Revenues, percentage	9.00%	61.00%
Eni SPA [Member]
Product Information [Line Items]
Revenues, percentage	1.00%	22.00%
Other [Member]
Product Information [Line Items]
Revenues, percentage	41.00%	17.00%
Customers [Member]
Product Information [Line Items]
Revenues, percentage	100.00%	100.00%

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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+ References

No definition available.

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