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Schedule of Unrealized Loss on Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Dec. 29, 2018 | Dec. 30, 2017
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Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | $ 45,960 | $ 43,186
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 354 | 224
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 43,423 | 14,648
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 863 | 116
Available-for-sale investments with unrealized losses, Fair Value, Total | 89,383 | 57,834
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 1,217 | 340
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value |  | 1,864
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss |  | 4
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 620 | 632
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 4 | 1
Available-for-sale investments with unrealized losses, Fair Value, Total | 620 | 2,496
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 4 | 5
Corporate bonds and direct obligations of government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | 45,960 | 41,322
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 354 | 220
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 42,803 | 14,016
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 859 | 115
Available-for-sale investments with unrealized losses, Fair Value, Total | 88,763 | 55,338
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | $ 1,213 | $ 335

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References No definition available. + Details
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