Note 10 - Cash Dividends (Details Textual) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended
Aug. 31, 2025	Mar. 31, 2025	Mar. 31, 2024
Payments of Dividends, Total		$ 6.0	$ 5.7
Dividends Payable		$ 0.1	$ 0.1
O 2026 Q1 Dividends [Member] \| Subsequent Event [Member]
Dividends Payable, Date Declared	Aug. 20, 2025
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.05
Dividends Payable, Date to be Paid	Sep. 10, 2025
Dividends Payable, Date of Record	Sep. 02, 2025

Aggregate dividends declared during the period for each share of common stock outstanding.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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