Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements of Operations [Abstract]
Sales	$ 139,725	$ 134,954	$ 194,294	$ 187,893
Costs and expenses
Cost of sales	99,663	94,849	140,096	134,354
Selling, general and administrative expenses	23,528	23,360	43,087	44,886
Interest expense, net	111	384	154	593
Other expense (income), net	119	(22)	137	(10)
Total costs and expenses	123,421	118,571	183,474	179,823
Income from continuing operations before income taxes	16,304	16,383	10,820	8,070
Income tax expense	5,990	5,859	3,953	2,877
Income from continuing operations	10,314	10,524	6,867	5,193
Income (loss) from discontinued operations, net of tax	5,171	(2,059)	1,049	(2,465)
Net income	$ 15,485	$ 8,465	$ 7,916	$ 2,728
Basic:
Continuing operations	$ 1.06	$ 1.09	$ 0.71	$ 0.54
Discontinued operations	$ 0.53	$ (0.21)	$ 0.11	$ (0.25)
Total	$ 1.59	$ 0.87	$ 0.81	$ 0.28
Diluted:
Continuing operations	$ 1.06	$ 1.08	$ 0.70	$ 0.54
Discontinued operations	$ 0.53	$ (0.21)	$ 0.11	$ (0.25)
Total	$ 1.59	$ 0.87	$ 0.81	$ 0.28
Weighted average shares outstanding
Basic	9,741	9,696	9,738	9,690
Diluted	9,747	9,702	9,743	9,702
Cash dividends per share of common stock	$ 0.15	$ 0.15	$ 0.30	$ 0.30