Note 4 - Capital Assets - Schedule of Capital Assets (Details) - USD ($) $ in Thousands	Nov. 30, 2022	May 31, 2022	Mar. 31, 2022
Property, plant and equipment, gross	$ 695,073	$ 754,740
Less: accumulated amortization	(155,949)	(167,241)
Total	539,124	587,499	$ 587,499
Land [Member]
Property, plant and equipment, gross	28,967	31,882
Manufacturing Facility [Member]
Property, plant and equipment, gross	430,631	453,412
Equipment [Member]
Property, plant and equipment, gross	219,282	254,486
Leasehold Improvements [Member]
Property, plant and equipment, gross	7,772	7,455
Construction in Progress [Member]
Property, plant and equipment, gross	$ 8,421	$ 7,505

Amount of accumulated depreciation and amortization from plant, property, and equipment and right-of-use asset from finance lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Amount, after accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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