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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Stock Plans (Details) - Stock Option Plans - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 26, 2015
Sep. 27, 2014
Sep. 26, 2015
Sep. 27, 2014
Defined Benefit Plan Disclosure [Line Items]        
Shares of common stock available for issuance (in shares) 1,223,563   1,223,563  
Compensation expense $ 1,283 $ 1,242 $ 3,936 $ 3,767
Income tax benefits $ 494 $ 478 $ 1,515 $ 1,450
Minimum        
Defined Benefit Plan Disclosure [Line Items]        
Vesting period of options     3 years  
Expiration period of grant     6 years  
Maximum        
Defined Benefit Plan Disclosure [Line Items]        
Vesting period of options     6 years  
Expiration period of grant     10 years