SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Property and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 40,931	$ 39,801
Less accumulated depreciation and amortization	27,863	25,649
Property and equipment, net	13,068	14,152
Depreciation expense	2,300	2,400
Cost of Sales [Member]
Property, Plant and Equipment, Net [Abstract]
Depreciation expense	2,200	2,200
General and Administrative Expense [Member]
Property, Plant and Equipment, Net [Abstract]
Depreciation expense	100	200
Land [Member]
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	4,993	4,993
Equipment and vehicles [Member]
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 26,606	25,363
Equipment and vehicles [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Life	1 year
Equipment and vehicles [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Life	10 years
Office equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 1,624	1,624
Office equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Life	1 year
Office equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Life	7 years
Building and leasehold improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 7,708	$ 7,821
Building and leasehold improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Life	5 years
Building and leasehold improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Life	40 years