CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net income	$ 6,091	$ 26,134	$ 12,462
Adjustments to reconcile net income to net cash (used in)
Depreciation	1,327	1,190	1,203
Amortization of intangible assets	227	290	359
Stock-based compensation	813	753	618
Amortization of debt issue costs	62	157	243
Loss on debt extinguishment		90
Deferred income tax benefit	1,980	(19,860)	75
(Gain) loss on sale of property and equipment	(77)	1	10
Provision for inventory reserves	623	275	205
Provision for bad debts	10
Other	26	106	57
Changes in operating assets and liabilities:
Accounts receivable	4,407	(2,384)	3,616
Revenue earned but not billed	851	(2,370)	3,186
Inventories	(420)	(5,322)	(1,319)
Prepaid expenses and other assets	(888)	(396)	66
Accounts payable	(8,125)	(2,637)	(79)
Accrued expenses and other liabilities	(6,933)	5,797	(192)
Deferred revenue, current and long-term	(87)	(95)	(92)
Net cash (used in) provided by operating activities	(113)	1,729	20,343
Investing activities
Cash paid for acquisition	(4,012)
Cash paid for investment	(500)
Purchase of property and equipment	(518)	(902)	(814)
Additions to patents and licenses	(10)	(51)	(131)
Proceeds from sales of property, plant and equipment	122	7	9
Net cash used in investing activities	(4,918)	(946)	(936)
Financing activities
Payment of long-term debt	(14)	(35)	(92)
Proceeds from revolving credit facility		8,000	74,100
Payment of revolving credit facility		(18,013)	(73,289)
Payments to settle employee tax withholdings on stock-based compensation	(5)	(84)	(76)
Debt issue costs	(4)	(245)	(91)
Net proceeds from employee equity exercises	127	236	63
Net cash provided by (used in) financing activities	104	(10,141)	615
Net (decrease) increase in cash and cash equivalents	(4,927)	(9,358)	20,022
Cash and cash equivalents at beginning of period	19,393	28,751	8,729
Cash and cash equivalents at end of period	14,466	19,393	28,751
Supplemental cash flow information:
Cash paid for interest	(68)	(118)	(254)
Cash paid for income taxes	$ (203)	(175)	(28)
Supplemental disclosure of non-cash investing and financing activities:
Operating lease assets obtained in exchange for new operating lease liabilities		$ 355	$ 2,757