CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ (4,751)	$ (5,120)	$ 1,926
Adjustments to reconcile net income (loss) to net cash provided by operating activites:
Depreciation	6,084	4,994	3,540
Amortization of intangibles	3,762	3,557	2,232
Impairment of long-lived assets	15	640	0
Amortization of capitalized software	591	456	341
Net accretion of discount and amortization of premium on marketable securities	219	740	896
Stock-based compensation	21,462	16,334	9,347
Tax benefit from stock-based compensation	(486)	(224)	(151)
Deferred income tax (benefit) provision	(411)	(1,493)	2,390
Other	977	533	256
Changes in assets and liabilities:
Accounts receivable, net	(4,799)	(4,539)	(1,529)
Inventory	(430)	136	52
Other current and non-current assets	(2,025)	(1,432)	(196)
Deferred cost of goods sold	(60)	(224)	(207)
Accounts payable	4,173	2,473	610
Accrued compensation	1,615	3,566	1,632
Accrued warranty	(2)	(13)	(321)
Accrued taxes	247	2,292	490
Accrued outside commissions	734	1,744	(5)
Deferred revenue	195	(273)	(1,065)
Other current and non-current liabilities	1,368	(580)	1,002
Net cash provided by operating activities	28,478	23,567	21,240
Cash flows from investing activities:
Acquisitions of property and equipment	(8,851)	(4,894)	(5,826)
Cost of capitalized software	(5,516)	(2,095)	(724)
Purchase of investments - available for sale	(140,026)	(126,723)	(106,021)
Sales of investments - available for sale	41,288	56,302	36,764
Proceeds from maturities of investments	93,795	64,361	63,546
Acquisition of businesses, net of cash acquired	(2,884)	(23,246)	0
Net cash used in investing activities	(22,194)	(36,295)	(12,261)
Cash flows from financing activities:
Capital lease payments	(674)	(446)	(149)
Payment of contingent consideration	(300)	(200)	0
Repurchase of common stock	(3,003)	(11,653)	(19,371)
Tax benefit from stock-based compensation expense	486	224	151
Proceeds from issuance of common stock under employee stock plans	5,087	4,827	4,455
Net cash provided by (used in) financing activities	1,596	(7,248)	(14,914)
Effect of exchange rate changes on cash	(426)	442	(114)
Net increase (decrease) in cash and cash equivalents	7,454	(19,534)	(6,049)
Cash and cash equivalents,beginning of year	33,576	53,110	59,159
Cash and cash equivalents, end of year	41,030	33,576	53,110
Supplemental and non-cash disclosures:
Acquisition of property and equipment, net in connection with acquisitions of businesses	0	1,453	0
Acquisition of capital lease in connection with acquisitions of businesses	0	1,332	0
Equipment acquired under capital leases	1,152	573	0
Cash paid for interest	16	44	5
Cash paid for income taxes	$ 460	$ 445	$ 159