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Marketable Securities (Details Narrative) $ in Thousands | 12 Months Ended
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Dec. 30, 2017 USD ($)
Investments, Debt and Equity Securities [Abstract] |
Unrealized loss position amortized cost | $ 1,348,777
Unrealized loss position fair value | $ 1,323,807
Percentage of available-for-sale securities in unrealized loss positions | 80.00%

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- Definition Amount of unrealized loss on securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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