Consolidated Statements of Net Earnings (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Interest income	$ 699	$ 528	$ 63

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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