GOODWILL AND INTANGIBLE ASSETS - Schedule of intangible assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Original Amount	$ 5,536	$ 5,518
Accumulated Amortization	(2,475)	(2,322)
Total	$ 3,061	3,196
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	7 years
Original Amount	$ 3,007	3,007
Accumulated Amortization	(1,456)	(1,348)
Total	1,551	1,659
Permits
Finite-Lived Intangible Assets [Line Items]
Original Amount	1,722	1,704
Accumulated Amortization	(518)	(492)
Total	$ 1,204	1,212
Permits | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	6 years
Permits | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	15 years
Patents
Finite-Lived Intangible Assets [Line Items]
Original Amount	$ 420	420
Accumulated Amortization	(300)	(296)
Total	$ 120	124
Patents | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	5 years
Patents | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	17 years
Trade name
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	7 years
Original Amount	$ 270	270
Accumulated Amortization	(125)	(116)
Total	$ 145	154
Non-compete
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	5 years
Original Amount	$ 117	117
Accumulated Amortization	(76)	(70)
Total	$ 41	$ 47