SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - A/R, Inventories, and Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Accounts Receivable and Allowance for Doubtful Accounts
Accounts Receivable Allowances	$ 204		$ 204		$ 209
Inventories
Raw Materials	15,595		15,595		13,870
Work in Process	437		437		3,112
Finished Goods	166		166		2,389
Reserves	(962)		(962)		(844)
Total	15,236		15,236		18,527	[1]
Impairment Analysis
Impairment charges recognized	0	$ 0	0	$ 0
Finite-Lived Intangible Assets
Gross Carrying Amount	2,233		2,233		2,230
Accumulated Amortization Amount	655		655		491
Net Book Value Amount	1,578		1,578		$ 1,739	[1]
Amortization expense	55	$ 76	164	$ 182
Estimated future annual amortization expense
Remainder of 2018	164		164
2019	208		208
2020	185		185
2021	185		185
2022	185		185
Thereafter	634		634
Total	1,561		$ 1,561
Customer Relationships
Finite-Lived Intangible Assets
Remaining lives			9 years		9 years
Gross Carrying Amount	1,302		$ 1,302		$ 1,302
Accumulated Amortization Amount	470		470		361
Net Book Value Amount	832		$ 832		$ 941
Trade Names
Finite-Lived Intangible Assets
Remaining lives			3 years		20 years
Gross Carrying Amount	100		$ 100		$ 814
Accumulated Amortization Amount	53		53		102
Net Book Value Amount	47		$ 47		$ 712
Intellectual Property
Finite-Lived Intangible Assets
Remaining lives			20 years		3 years
Gross Carrying Amount	814		$ 814		$ 100
Accumulated Amortization Amount	132		132		28
Net Book Value Amount	682		$ 682		$ 72
Patents
Finite-Lived Intangible Assets
Remaining lives			7 years		7 years
Gross Carrying Amount	17		$ 17		$ 14
Net Book Value Amount	$ 17		$ 17		$ 14

[1] The balance sheet at December 31, 2017 has been derived from the audited financial statements at that date