ACCOUNTS RECEIVABLE (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ACCOUNTS RECEIVABLE
Accounts receivable, gross	$ 31,333	$ 30,141
Less: allowance for doubtful accounts	(1,253)	(1,999)
Accounts receivable, net	30,080	28,142
Freight rebates receivable
ACCOUNTS RECEIVABLE
Accounts receivable, gross	8,527	7,106
Credit card receivables
ACCOUNTS RECEIVABLE
Accounts receivable, gross	8,480	10,243
Accounts receivable, trade
ACCOUNTS RECEIVABLE
Accounts receivable, gross	8,317	9,054
Other receivables
ACCOUNTS RECEIVABLE
Accounts receivable, gross	$ 6,009	$ 3,738