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Consolidated Statements of Stockholders' Equity (Parentheticals) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Mar. 31, 2016
Cumulative Preferred Stock [Member] |  |  |
Preferred stock, dividend rate | 6.00% | 6.00% | 6.00%
Preferred stock, par value (in dollars per share) | $ 0.25 | $ 0.25 | $ 0.25
Cumulative Convertible Preferred Stock [Member] |  |  |
Preferred stock, dividend rate | 10.00% | 10.00% | 10.00%
Preferred stock, par value (in dollars per share) | $ 0.025 | $ 0.025 | $ 0.025
Participating Convertible Preferred Stock [Member] |  |  |
Preferred stock, par value (in dollars per share) | 0.025 | 0.025 | 0.025
Series 2003 Convertible Preferred Stock [Member] |  |  |
Preferred stock, par value (in dollars per share) | 0.025 | 0.025 | 0.025
Common Class A [Member] |  |  |
Common Stock, Par Value (in dollars per share) | 0.25 | 0.25 | 0.25
Common Class B [Member] |  |  |
Common Stock, Par Value (in dollars per share) | $ 0.25 | $ 0.25 | $ 0.25
AOCI Attributable to Parent [Member] |  |  |
Change in pension and postretirement benefits adjustment, tax | $ 3,774 | $ 10,367 | $ 2,179

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