Note 4. Acquisition (Details) (USD $)
 0 Months Ended 3 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 5 Months Ended
Aug. 01, 2013
Dec. 28, 2014
Sep. 28, 2014
Jun. 29, 2014
Mar. 30, 2014
Dec. 29, 2013
Sep. 29, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 29, 2013
Aug. 01, 2013
Dec. 28, 2014
Dec. 29, 2013
Note 4. Acquisition (Details) [Line Items]                          
Business Combination, Consideration Transferred $ 158,543,000                        
Business Combination, Bargain Purchase, Gain Recognized, Amount 7,950,000    [1]    [1]    [1]    [1] (255,000) [1] 8,205,000 [1]    [1]    [1] 7,950,000      
Japan Employees Compensation and Benefits Liability [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other   8,800,000                   8,800,000  
Net of Cash Acquired [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Business Combination, Consideration Transferred                     150,000,000    
Developed Technology [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Fair Value Inputs, Discount Rate                       24.00%  
In Process Research and Development [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Fair Value Inputs, Discount Rate                       26.00%  
Customer Relationships [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Fair Value Inputs, Discount Rate                       24.00%  
Trademarks [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Fair Value Inputs, Discount Rate                       24.00%  
Trade Names [Member] | Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Fair Value Inputs, Discount Rate                       24.00%  
Fujitsu Semiconductor Limited [Member]                          
Note 4. Acquisition (Details) [Line Items]                          
Business Combination, Consideration Transferred                     158,500,000    
Business Combination, Bargain Purchase, Gain Recognized, Amount                   8,000,000      
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual                         $ 222,800,000
[1] The gain for the quarter ended September 29, 2013 and December 29, 2013, relates to the gain and related adjustments on acquistion of the MCA business. The accounting guidance requires that the economic gain resulting from the fair value received being greater than the consideration paid to acquire the net assets to be recorded as an one-time gain included in earnings.