Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Share data	3 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidated Statements of Operations [Abstract]
Product revenue	$ 21,679	$ 15,758
Service revenue	1,095	1,219
Total revenue	22,774	16,977
Cost of product revenue	15,004	10,307
Cost of service revenue	734	917
Total cost of revenue	15,738	11,224
Gross profit	7,036	5,753
Operating expenses:
General and administrative	3,076	2,945
Sales and marketing	3,768	3,590
Research and development	622	610
Total operating expenses	7,466	7,145
Loss from operations	(430)	(1,392)
Other income (expense):
Interest expense	(87)	(70)
Dividend and interest income	154	93
Total other income	67	23
Loss before income tax	(363)	(1,369)
Income tax benefit	(144)	(833)
Net loss	$ (219)	$ (536)
Basic net loss per share attributable to common shareholders	$ (0.01)	$ (0.02)
Weighted-average common shares outstanding	22,921,436	22,523,107
Diluted net loss per share attributable to common shareholders	$ (0.01)	$ (0.02)
Weighted-average common shares and share equivalents outstanding	22,921,436	22,523,107