GOODWILL AND OTHER INTANGIBLE ASSETS - Other intangible assets (Details) - USD ($)		6 Months Ended	12 Months Ended
		Jun. 30, 2019	Dec. 31, 2018
Other intangible assets:
Cost		$ 11,294,000	$ 11,297,000
Accumulated amortization		3,839,000	3,497,000
Net book value		7,455,000	7,800,000
Customer Relationships [Member]
Other intangible assets:
Cost	[1]	6,820,000	6,821,000
Accumulated amortization	[1]	2,418,000	2,135,000
Net book value	[1]	$ 4,402,000	$ 4,686,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		8 years 9 months 18 days	9 years 3 months 18 days
Trademarks and trade names one [Member]
Other intangible assets:
Cost	[1]	$ 2,307,000	$ 2,308,000
Accumulated amortization	[1]	0	0
Net book value	[1]	$ 2,307,000	$ 2,308,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		12 years	12 years 6 months
Engineering drawings [Member]
Other intangible assets:
Cost		$ 330,000	$ 330,000
Accumulated amortization		216,000	202,000
Net book value		$ 114,000	$ 128,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years 6 months	7 years 8 months 12 days
Non-compete [Member]
Other intangible assets:
Cost	[1]	$ 232,000	$ 233,000
Accumulated amortization	[1]	225,000	223,000
Net book value	[1]	$ 7,000	$ 10,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		1 year 9 months 18 days	2 years 3 months 18 days
Patents [Member]
Other intangible assets:
Cost		$ 1,405,000	$ 1,405,000
Accumulated amortization		941,000	905,000
Net book value		$ 464,000	$ 500,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years 6 months	7 years 10 months 24 days
Trademarks And Trade Names Two [Member]
Other intangible assets:
Cost		$ 200,000	$ 200,000
Accumulated amortization		39,000	32,000
Net book value		$ 161,000	$ 168,000

[1] (1)A portion of these intangibles are maintained in a foreign currency and are therefore subject to foreign exchange rate fluctuations.