CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Cash flows from operating activities:
Net income	$ 69,228	$ 6,494	$ 3,879
Adjustments to reconcile net income to net cash provided by operating activites:
Depreciation	1,535	1,235	998
Amortization	788	94	0
Stock-based compensation	1,506	458	204
Change in fair value of warrant liability	0	(167)	146
Deferred income tax benefit	(62,422)	0	0
Other	561	84	(306)
Changes in assets and liabilities:
Accounts receivable, net	(1,059)	(358)	(253)
Inventory	1,535	29	545
Other current and noncurrent assets	489	75	41
Deferred cost of goods sold	1	(16)	86
Accounts payable	(1,214)	916	(1,323)
Accrued compensation	128	278	180
Accrued warranty	25	31	3
Accrued taxes	(356)	24	27
Deferred revenue	(197)	(475)	(944)
Other current and noncurrent liabilities	(1,337)	(113)	(792)
Net cash provided by operating activities	9,211	8,589	2,491
Cash flows from investing activities:
Purchases of property and equipment	(2,300)	(2,057)	(1,052)
Restricted cash decrease	28	0	100
Purchase of investments	0	(2,000)	0
Purchase of strategic investment	0	(315)	0
Acquisition of businesses, net of cash acquired	(713)	(998)	0
Sale of property and equipment	0	6	4
Net cash used in investing activities	(2,985)	(5,364)	(948)
Cash flows from financing activities:
Capital lease payments	(275)	(38)	(50)
Repurchase of common stock	(2,550)	(7,662)	(212)
Buyback of employee stock options and stock purchase rights	(384)	(539)	0
Proceeds from exercise of warrants	0	880	0
Proceeds from issuance of common stock	(60)	278	0
Proceeds from issuance of common stock under employee stock plans	2,995	2,274	399
Net cash provided by (used in) financing activities	(274)	(4,807)	137
Net increase (decrease) in cash and cash equivalents	5,952	(1,582)	1,680
Cash and cash equivalents. beginning of year	16,474	18,056	16,376
Cash and cash equivalents, end of year	22,426	16,474	18,056
Supplemental and non-cash disclosures:
Issuance of common stock in connection with acquisitions of businesses	31,358	600	0
Fair value of options assumed in connection with acquisitions of businesses	274	0	0
Acquisition of property and equipment, net in connection with acquisitions of businesses	364	80	0
Acquisition of capital lease in connection with acquisitions of businesses	317	0	0
Transfer of net assets in purchase of strategic investment	0	41	0
Assets acquired under capital lease	45	0	46
Interest paid	5	10	29
Income taxes paid	$ 94	$ 6	$ 105