SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Advertising cost
Advertising	$ 57,705	$ 54,909	$ 55,282
Cash and Cash Equivalents
Maximum original maturity period of cash equivalents	3 months
Cash held at various banking institutions	$ 134,574	108,372	$ 118,216	$ 65,082
Cash held in non-interest-bearing accounts	99,800
Cash held in foreign bank accounts	$ 34,816	$ 35,065