XML 19 R55.htm IDEA: XBRL DOCUMENT v2.4.1.9
Employee Benefit Plan (Details) (USD $)
 12 Months Ended
Dec. 27, 2014
Dec. 28, 2013
Dec. 29, 2012
Schedule of Benefit Plans Disclosure [Line Items]      
Employee age threshhold for higher annual contribution 50 years    
Employer matching percentage 50.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent    
Maximum amount of employee contribution that employer matches 6.00%us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent    
Amount charged to operations in connection with the plan $ 224,000us-gaap_DefinedContributionPlanCostRecognized $ 146,000us-gaap_DefinedContributionPlanCostRecognized $ 210,000us-gaap_DefinedContributionPlanCostRecognized
Under the age of 50      
Schedule of Benefit Plans Disclosure [Line Items]      
Maximum amount of annual compensation that can be deferred 17,500us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeeAmount
/ kopn_AgeLimitAxis
= kopn_UnderAgeFiftyMember		    
Over the age fo 50      
Schedule of Benefit Plans Disclosure [Line Items]      
Maximum amount of annual compensation that can be deferred $ 23,000us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeeAmount
/ kopn_AgeLimitAxis
= kopn_OverAgeFiftyMember