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Investments Investments (Details Textual 2) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 28, 2019 | Dec. 29, 2018
Other Investment Not Readily Marketable [Line Items] |  |
Non-marketable investments | $ 138,212 | $ 118,734
Other equity investments not readily marketable [Member] |  |
Other Investment Not Readily Marketable [Line Items] |  |
Non-marketable investments | 1,900 | 2,800
Net gains on equity securities without readily determinable fair value | 2,100 | 3,300
Unrealized gains (losses) for the period that relate to equity securities without readily determinable fair values still held at the reporting date. | $ 900 | $ 100

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- Definition Gains (Losses) for the period that relate to equity securities without readily determinable fair values still held at the reporting date. + References No definition available. + Details
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- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117539-209714 + Details
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- Definition Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117539-209714 + Details
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