INTANGIBLE ASSETS, NET - Amortization Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Amortization of Deferred Charges [Abstract]
Total amortization expenses	$ 750	$ 650	$ 1,452	$ 1,367
Referral Relationships [Member]
Amortization of Deferred Charges [Abstract]
Total amortization expenses	581	559	1,114	1,079
Non-compete Agreements [Member]
Amortization of Deferred Charges [Abstract]
Total amortization expenses	$ 169	$ 91	$ 338	$ 288