Consolidated Statement Of Changes in Shareholders' Equity - 3 months ended Jun. 30, 2018 - USD ($) $ in Thousands		Class C Convertible Preferred Stock [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Total
Balance beginning at Mar. 31, 2018		$ 33	$ 392	$ (106,563)	$ 199,576	$ (4,248)	$ 539,286	$ 628,476
Beginning balance, preferred shares at Mar. 31, 2018		21,802						21,802
Beginning balance, common shares at Mar. 31, 2018			39,166,000	6,330,000
Net income							20,644	$ 20,644
Other comprehensive loss:
Pension liability adjustment [($101) pre-tax]						(77)		(77)
Cash dividends:
Preferred dividends	[1]						(102)	(102)
Common dividends	[1]						(6,572)	(6,572)
Dividend payable							(12)	(12)
Exercise of stock options				$ (445)	1,223			778
Exercise of stock options, shares			38,000	8,000
Stock-based compensation					1,084			1,084
Balance ending at Jun. 30, 2018		$ 33	$ 392	$ (107,008)	$ 201,883	$ (4,325)	$ 553,244	$ 644,219
Ending balance, preferred shares at Jun. 30, 2018		21,802						21,802
Ending balance, common shares at Jun. 30, 2018			39,204,000	6,338,000

[1] First quarter fiscal year 2019 dividend payment of $.20 per common share or common share equivalent paid on June 14, 2018.