5. INCOME TAXES - Unrecognized tax benefits (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
INCOME TAXES
Unrecognized tax benefits, noncurrent		$ 619,000	$ 244,000
Deferred tax assets unrecognized tax benefit		$ 2,100,000	2,500,000
Corporate income tax rate	35.00%	21.00%
Net deferred tax assets		$ 5,988,000	8,946,000
Valuation allowance		(5,913,000)	(8,939,000)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning of period		2,714,000	2,055,000	$ 1,982,000
Additions based on tax positions related to current year		520,000	730,000	453,000
Additions based on tax positions related to prior years				183,000
2017 Tax Act and tax rate re-measurement		(499,000)
Lapses during the current year applicable to statutes of limitations			(71,000)	(563,000)
Unrecognized tax benefits, end of period		2,735,000	$ 2,714,000	$ 2,055,000
Unrecognized tax benefit that would impact effective tax rate		$ 601,000