Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Consolidated Statements of Operations [Abstract]
Sales	$ 116,020	$ 129,240	$ 310,572	$ 323,534
Costs and expenses
Cost of sales	78,407	87,662	214,930	227,758
Selling, general and administrative expenses	20,510	22,446	61,934	65,533
Disposition of product line, net	0	0	5,798	0
Interest (income) expense, net	(1)	73	(68)	227
Other expense, net	85	202	33	339
Total costs and expenses	99,001	110,383	282,627	293,857
Income from continuing operations before income taxes	17,019	18,857	27,945	29,677
Income tax expense	5,419	6,748	10,372	10,701
Income from continuing operations	11,600	12,109	17,573	18,976
Income (loss) from discontinued operations, net of tax	11	(1,131)	55	(82)
Net income	$ 11,611	$ 10,978	$ 17,628	$ 18,894
Basic:
Continuing operations	$ 1.21	$ 1.25	$ 1.83	$ 1.95
Discontinued operations	$ 0.00	$ (0.12)	$ 0.01	$ (0.01)
Total	$ 1.22	$ 1.13	$ 1.84	$ 1.94
Diluted:
Continuing operations	$ 1.21	$ 1.24	$ 1.83	$ 1.95
Discontinued operations	$ 0.00	$ (0.12)	$ 0.01	$ (0.01)
Total	$ 1.22	$ 1.13	$ 1.84	$ 1.94
Weighted average shares outstanding
Basic	9,548	9,723	9,594	9,733
Diluted	9,554	9,732	9,597	9,739
Cash dividends per share of common stock	$ 0.15	$ 0.15	$ 0.45	$ 0.45