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Cash, Cash Equivalents, and Investments - Gross Unrealized Losses and Fair Values for Available-for-Sale Investments (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 29, 2013
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Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | $ 127,545
Unrealized Losses, Less than 12 Months | (415)
Fair Value, 12 Months or Greater | 19,675
Unrealized Losses, 12 Months or Greater | (456)
Total Fair Value | 147,220
Total Unrealized Losses | (871)
Corporate Bonds [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | 62,910
Unrealized Losses, Less than 12 Months | (272)
Fair Value, 12 Months or Greater | 2,455
Unrealized Losses, 12 Months or Greater | (1)
Total Fair Value | 65,365
Total Unrealized Losses | (273)
Asset-Backed Securities [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | 41,848
Unrealized Losses, Less than 12 Months | (102)
Fair Value, 12 Months or Greater | 16,332
Unrealized Losses, 12 Months or Greater | (397)
Total Fair Value | 58,180
Total Unrealized Losses | (499)
Sovereign Bonds [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | 9,300
Unrealized Losses, Less than 12 Months | (25)
Fair Value, 12 Months or Greater | 888
Unrealized Losses, 12 Months or Greater | (58)
Total Fair Value | 10,188
Total Unrealized Losses | (83)
Treasury Bills [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | 7,614
Unrealized Losses, Less than 12 Months | (5)
Total Fair Value | 7,614
Total Unrealized Losses | (5)
Municipal Bonds [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | 4,374
Unrealized Losses, Less than 12 Months | (10)
Total Fair Value | 4,374
Total Unrealized Losses | (10)
Agency Bonds [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Fair Value, Less than 12 Months | 1,499
Unrealized Losses, Less than 12 Months | (1)
Total Fair Value | 1,499
Total Unrealized Losses | $ (1)

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