Unaudited Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Product revenue	$ 17,675	$ 14,982	$ 33,027	$ 30,778
Service revenue	995	746	1,277	1,538
Total revenue	18,670	15,728	34,304	32,316
Cost of product revenue	11,752	12,301	23,171	24,414
Cost of service revenue	674	515	863	1,232
Total cost of revenue	12,426	12,816	24,034	25,646
Gross profit	6,244	2,912	10,270	6,670
Operating expenses:
General and administrative	3,598	3,403	7,499	7,274
Sales and marketing	3,125	2,634	6,020	5,703
Research and development	517	441	998	863
Total operating expenses	7,240	6,478	14,517	13,840
Loss from operations	(996)	(3,566)	(4,247)	(7,170)
Other income (expense):
Other income	90	0	190	0
Interest expense	(68)	(60)	(138)	(151)
Interest income	14	32	24	80
Total other income (expense)	36	(28)	76	(71)
Loss before income tax	(960)	(3,594)	(4,171)	(7,241)
Income tax expense (benefit)	10	6	(261)	11
Net loss and comprehensive loss	$ (970)	$ (3,600)	$ (3,910)	$ (7,252)
Basic net loss per share attributable to common shareholders (in dollars per share)	$ (0.03)	$ (0.13)	$ (0.14)	$ (0.26)
Weighted-average common shares outstanding (in shares)	28,171,899	27,598,492	28,029,526	27,540,378
Diluted net loss per share (in dollars per share)	$ (0.03)	$ (0.13)	$ (0.14)	$ (0.26)
Weighted-average common shares and share equivalents outstanding (in shares)	28,171,899	27,598,492	28,029,526	27,540,378