Investments (Schedule Of Held-To-Maturity Securities) (Details) - USD ($) |
Sep. 28, 2019 |
Dec. 29, 2018 |
|---|---|---|
| Schedule of Held-to-maturity Securities [Line Items] | ||
| Amortized Cost | $ 0 | $ 63,539,000 |
| Unrecognized Holding Gains | 1,000 | |
| Unrecognized Holding Losses | (46,000) | |
| Estimated Fair Value | 63,494,000 | |
| Corporate Bonds [Member] | ||
| Schedule of Held-to-maturity Securities [Line Items] | ||
| Amortized Cost | 57,554,000 | |
| Unrecognized Holding Gains | 1,000 | |
| Unrecognized Holding Losses | (46,000) | |
| Estimated Fair Value | 57,509,000 | |
| Commercial Paper [Member] | ||
| Schedule of Held-to-maturity Securities [Line Items] | ||
| Amortized Cost | 5,985,000 | |
| Estimated Fair Value | $ 5,985,000 |
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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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