Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Balance at Mar. 31, 2019	$ 34,055	$ 3,338	$ 142,260	$ (111,543)
Balance (in shares) at Mar. 31, 2019		33,377
Increase (Decrease) in Stockholders' Equity
Stock option exercises	14	$ 1	13
Stock option exercises (in shares)		10
Issuance of shares pursuant to Employee Stock Purchase Plan	172	$ 5	167
Issuance of shares pursuant to Employee Stock Purchase Plan (in Shares)		48
Stock-based compensation	602		602
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes (in shares)		2
Issuance of common stock in connection with public offering	26,751	$ 618	26,133
Issuance of common stock in connection with public offering (in shares)		6,183
Net income (loss)	(1,572)			(1,572)
Balance at Jun. 30, 2019	60,022	$ 3,962	169,175	(113,115)
Balance (in shares) at Jun. 30, 2019		39,620
Balance at Mar. 31, 2019	34,055	$ 3,338	142,260	(111,543)
Balance (in shares) at Mar. 31, 2019		33,377
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(3,759)
Balance at Sep. 30, 2019	63,230	$ 4,057	174,475	(115,302)
Balance (in shares) at Sep. 30, 2019		40,571
Balance at Jun. 30, 2019	60,022	$ 3,962	169,175	(113,115)
Balance (in shares) at Jun. 30, 2019		39,620
Increase (Decrease) in Stockholders' Equity
Stock option exercises	67	$ 2	65
Stock option exercises (in shares)		23
Issuance of shares pursuant to Employee Stock Purchase Plan	793	$ 0	793
Issuance of shares pursuant to Employee Stock Purchase Plan (in Shares)		0
Stock-based compensation		$ 6	(6)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		59
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes	4,535	$ 87	4,448
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes (in shares)		869
Net income (loss)	(2,187)			(2,187)
Balance at Sep. 30, 2019	63,230	$ 4,057	174,475	(115,302)
Balance (in shares) at Sep. 30, 2019		40,571
Balance at Mar. 31, 2020	$ 63,127	$ 4,071	176,209	(117,153)
Balance (in shares) at Mar. 31, 2020	40,713	40,713
Increase (Decrease) in Stockholders' Equity
Stock option exercises	$ 74	$ 3	71
Stock option exercises (in shares)		27
Stock-based compensation	607		607
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes		$ 1	(1)
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes (in shares)		12
Net income (loss)	10,348			10,348
Balance at Jun. 30, 2020	74,156	$ 4,075	176,886	(106,805)
Balance (in shares) at Jun. 30, 2020		40,752
Balance at Mar. 31, 2020	$ 63,127	$ 4,071	176,209	(117,153)
Balance (in shares) at Mar. 31, 2020	40,713	40,713
Increase (Decrease) in Stockholders' Equity
Net income (loss)	$ 10,761
Balance at Sep. 30, 2020	$ 76,046	$ 4,111	178,327	(106,392)
Balance (in shares) at Sep. 30, 2020	41,110	41,110
Balance at Jun. 30, 2020	$ 74,156	$ 4,075	176,886	(106,805)
Balance (in shares) at Jun. 30, 2020		40,752
Increase (Decrease) in Stockholders' Equity
Stock option exercises	622	$ 24	598
Stock option exercises (in shares)		239
Issuance of shares pursuant to Employee Stock Purchase Plan	188	$ 4	184
Issuance of shares pursuant to Employee Stock Purchase Plan (in Shares)		42
Stock-based compensation	667		667
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes		$ 8	(8)
Issuance of shares pursuant - to vesting of restricted stock units, net of payroll withholding taxes (in shares)		77
Net income (loss)	413			413
Balance at Sep. 30, 2020	$ 76,046	$ 4,111	$ 178,327	$ (106,392)
Balance (in shares) at Sep. 30, 2020	41,110	41,110