ACCOUNTS RECEIVABLE (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Receivables [Abstract]
Accounts receivable	$ 181,916,000	$ 205,084,000
Allowance for doubtful accounts	(4,527,000)	(5,706,000)	$ (5,287,000)	$ (5,130,000)
Accounts receivable, net	$ 177,389,000	$ 199,378,000