INCOME TAXES (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014
Effective income tax rate (as a percent)	38.00%	10.00%	36.00%	10.00%		8.40%
Reconciliation of federal income taxes and reported income taxes
Statutory federal tax provision (benefit)	$ (57,000)	$ 129,000	$ (327,000)	$ 259,000
State income taxes (benefits)	(6,000)	14,000	(32,000)	33,000
Income tax credits	(14,000)	(19,000)	(39,000)	(33,000)
Change in uncertain tax positions	(4,000)	1,000	(4,000)	(99,000)
Return to provision true-up	5,000	(84,000)	5,000	(84,000)
Other		(3,000)		(3,000)
Income tax expense (benefit)	(76,000)	38,000	(397,000)	73,000
Unrecognized tax benefits
Net uncertain tax benefit positions that would increase (reduce) effective income tax rate, if recognized	$ 51,750		$ 51,750			$ 56,000
Minnesota Tax Authority
Unrecognized tax benefits
Research and development credits		$ 100,000		$ 100,000
Forecast
Effective income tax rate (as a percent)					36.00%