SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Preferred Stock, Revenue Recognition, Product Warranties, Advertising, Net Income (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
Preferred Stock
Non-cumulative dividend rate (as a percent)	12.00%
Liquidation preference (in dollars per share)	$ 1.00
Preferred stock dividends declared (in dollars per share)	$ 0	$ 0
Revenues
Retained Earnings	$ 5,436	$ 3,889
Advertising
Advertising expense charged	$ 132	$ 68
Reconciliation of basic and diluted share amounts
Basic weighted average common shares outstanding	2,692,382	2,745,602
Weighted average common stock equivalents from assumed exercise of stock options (in shares)	7,232
Diluted weighted average common shares outstanding	2,699,614	2,745,602
Maximum
Revenues
Percentage of sales (as a percent)	10.00%	10.00%
Difference between Revenue Guidance in Effect before and after Topic 606 | ASU 2014-09
Revenues
Retained Earnings			$ 1,381