Note 10 - Retirement Plans - Pension and Post Retirement Plan Adjustments (Details) $ in Thousands	12 Months Ended
Mar. 31, 2021 USD ($)
Balance	$ 394,364
Other comprehensive income	60,153
Balance	577,815
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(79,220)
Balance	$ (19,067)

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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+ Details