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Investments (Schedule Of Held-To-Maturity Securities) (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 29, 2019 | Dec. 29, 2018
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 2,999 | $ 63,539
Unrecognized Holding Gains |  | 1
Unrecognized Holding Losses |  | (46)
Estimated Fair Value | $ 2,999 | 63,494
Held-to-maturity securities maturity period | 1 year |
Corporate Bonds [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 2,999 | 57,554
Unrecognized Holding Gains |  | 1
Unrecognized Holding Losses |  | (46)
Estimated Fair Value | $ 2,999 | 57,509
Commercial Paper [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost |  | 5,985
Estimated Fair Value |  | $ 5,985

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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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