SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Cash, Property equipment - (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 01, 2016	Dec. 31, 2014
Cash and Cash Equivalents
Uninsured deposits	$ 4,681	$ 4,183
Office and other equipment | Minimum
Cash and Cash Equivalents
Property, Plant and Equipment, Useful Life	2 years
Office and other equipment | Maximum
Cash and Cash Equivalents
Property, Plant and Equipment, Useful Life	10 years
Internally developed software
Cash and Cash Equivalents
Property, Plant and Equipment, Useful Life	3 years
Leasehold improvements | Minimum
Cash and Cash Equivalents
Property, Plant and Equipment, Useful Life	3 years
Leasehold improvements | Maximum
Cash and Cash Equivalents
Property, Plant and Equipment, Useful Life	10 years