NOTES PAYABLE TO BANKS (Detail Textuals 2) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Line Of Credit Facility [Line Items]
Other current assets	$ 5,924	$ 7,131
Revolving credit facility
Line Of Credit Facility [Line Items]
Loan origination fees and other debt related costs	3,000
Other current assets	61
Letter of credit facility
Line Of Credit Facility [Line Items]
Available borrowing under the facility	125,000
Letters of credit outstanding amount	19,600
Available credit facility	$ 105,400