CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities:
Net income (loss)	$ (3,252)	$ 886
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Allowance for sales returns, doubtful accounts and other	(2)	3
Provision for excess and obsolete inventories	739	333
Depreciation and amortization	625	821
Stock-based compensation	986	930
Amortization of premium on investments	47	33
Changes in assets and liabilities:
Accounts receivable	999	(1,332)
Inventory	(2)	(2,137)
Prepaid expenses and other assets	(151)	(107)
Accounts payable	297	685
Accrued expenses and other liabilities	(932)	1,023
Deferred revenue	361	(719)
Net cash (used) provided by operating activities	(285)	419
Cash flows from investing activities:
Purchase of investments	(5,248)	(9,410)
Maturities of short-term investments	7,500	12,100
Restricted cash	479
Purchases of property and equipment	(328)	(168)
Net cash provided by investing activities	2,403	2,522
Cash flows from financing activities:
Repurchase of common stock		(6,618)
Payment of escrow amount	(479)
Proceeds from issuance of common stock under employee stock plans	2,063	517
Net cash provided by (used in) financing activities	1,584	(6,101)
Net increase (decrease) in cash and cash equivalents	3,702	(3,160)
Cash and cash equivalents at beginning of the period	33,736	31,963
Cash and cash equivalents at end of the period	37,438	28,803
Non-cash financing activities:
Purchases of property and equipment through accounts payable and accruals	47
Supplemental cash flow information:
Net cash paid for income taxes	$ 30	$ 1,339