5. INCOME TAXES - Unrecognized tax benefits (Details) - USD ($)	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
INCOME TAXES
Unrecognized tax benefits, noncurrent	$ 244,000	$ 116,000
Deferred tax assets unrecognized tax benefit	2,481,000	1,943,000
Possible reduction in uncertain tax benefits	0
Net deferred tax assets	7,000
Net deferred tax liability		811,000
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning of period	2,055,000	1,982,000	$ 2,386,000
Additions based on tax positions related to current year	730,000	453,000	292,000
Additions based on tax positions related to prior years		183,000
Lapses during the current year applicable to statutes of limitations	(71,000)	(563,000)	(696,000)
Unrecognized tax benefits, end of period	2,714,000	$ 2,055,000	$ 1,982,000
Unrecognized tax benefit that would impact effective tax rate	$ 233,000