Note 11 - Inventories (Details Textual) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Inventory, LIFO Reserve, Effect on Income, Net, Total	$ (11.2)	$ 6.6	$ 18.0
Effect Of LIFO Earnings Per Share Basic	$ (1.15)	$ 0.67	$ 1.81
Effect Of LIFO Earnings Per Share Diluted	$ (1.15)	$ 0.67	$ 1.79

The effect of using the LIFO methond on the amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

No definition available.

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