11. STOCK-BASED COMPENSATION - Stock option activities (Details) - USD ($)	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
STOCK-BASED COMPENSATION
Shares available for grant, Beginning	1,331,562	2,522,314	3,426,548
Options reserved (in shares)	4,000,000
Granted (in shares)	(1,280,761)	(1,285,252)	(1,011,708)
Forfeited (in shares)	484,862	94,500	107,474
Shares available for grant, Ending	4,535,663	1,331,562	2,522,314
Number of Shares Underlying Options Outstanding
Balance at the beginning of the period (in shares)	8,432,877	8,135,791	8,017,029
Granted (in shares)	1,280,761	1,285,252	1,011,708
Exercised (in shares)	(316,784)	(667,503)	(772,667)
Forfeited (in shares)	(806,179)	(320,663)	(120,279)
Balance at the end of the period (in shares)	8,590,675	8,432,877	8,135,791
Options vested and exercisable (in shares)	5,499,074
Options vested and expected to vest (in shares)	8,498,505
Weighted Average Remaining Contractual Life
Options weighted average remaining contractual life	5 years 4 months 20 days
Options vested and expected to vest	5 years 4 months 6 days
Options vested and exercisable	3 years 9 months 7 days
Weighted Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 6.17	$ 6.17	$ 5.77
Granted (in dollars per share)	5.43	6.46	8.11
Exercised (in dollars per share)	5.12	5.99	4.39
Forfeited (in dollars per share)	6.45	7.84	7.03
Balance at the end of the period (in dollars per share)	6.07	$ 6.17	$ 6.17
Options vested and exercisable (in dollars per share)	5.86
Options vested and expected to vest (in dollars per share)	$ 6.07
Intrinsic Value
Exercised (in dollars)	$ 149,937	$ 961,633	$ 2,614,879
Options vested and exercisable (in dollars)	133,784
Options vested and expected to vest (in dollars)	$ 133,784