Discontinued Operations and Assets Held for Sale (Details) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	May 21, 2010
Results of discontinued operations [Abstract]
Net sales		$ 8,288,000		$ 24,813,000
Cost of sales		(9,871,000)		(25,192,000)
Operating expenses		(173,000)		(3,676,000)
Income tax benefit	0	88,000	0	76,000
Net loss from discontinued operations	0	(1,668,000)	0	(3,979,000)
Amount of assets disposed of in sale of various parts of the SST acquisition					$ 23,600,000