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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 5) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended | 32 Months Ended |
--- | --- | --- | --- | ---
May 31, 2014 | Dec. 31, 2016 | Dec. 26, 2015 | Dec. 27, 2014 | Dec. 31, 2016 | Feb. 28, 2015
Research and Development |  |  |  |  |  |
Research and development expenses |  | $ 8,300 | $ 11,600 | $ 13,900 |  |
Stock Repurchase Program |  |  |  |  |  |
Authorized amount | $ 500,000 |  |  |  |  | $ 250,000
Length of authorization period | 12 months |  |  |  |  |
Shares acquired under share repurchase program |  | 441,949 | 1,435,488 | 2,711,149 | 4,588,131 |
Amount paid for share repurchase |  | $ 53,800 | $ 168,983 | $ 395,045 | $ 617,800 |

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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 + Details
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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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