Note 7 - Indebtedness - Interest Expense on the Notes (Details) - The Notes [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Coupon interest expense at 1.375%	$ 335	$ 593	$ 1,037	$ 1,779
Amortization of debt issuance costs	134	231	412	692
Total interest and amortization of debt issuance costs	$ 469	$ 824	$ 1,449	$ 2,471

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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-Topic 835
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