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Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands | Jul. 01, 2018 | Dec. 31, 2017
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Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | $ 803,061 | $ 1,470,729
Available-for-sale marketable securities, Unrealized Gain | 707 | 6,582
Available-for-sale marketable securities, Unrealized (Loss) | (3,331) | (3,406)
Available-for-sale marketable securities, Fair Market Value | 800,437 | 1,473,905
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 691,584 | 1,350,895
U.S. Treasury Securities |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 530,944 | 858,258
Available-for-sale marketable securities, Unrealized Gain | 29 | 72
Available-for-sale marketable securities, Unrealized (Loss) | (2,116) | (2,535)
Available-for-sale marketable securities, Fair Market Value | 528,857 | 855,795
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 477,385 | 850,163
Commercial Paper |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 218,594 | 283,009
Available-for-sale marketable securities, Unrealized Gain | 9 | 18
Available-for-sale marketable securities, Unrealized (Loss) | (83) | (187)
Available-for-sale marketable securities, Fair Market Value | 218,520 | 282,840
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 184,349 | 258,933
Corporate Debt Securities |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 38,709 | 131,179
Available-for-sale marketable securities, Unrealized Gain | 668 | 2,380
Available-for-sale marketable securities, Unrealized (Loss) | (1,005) | (373)
Available-for-sale marketable securities, Fair Market Value | 38,372 | 133,186
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 20,956 | 91,010
U.S. Government Agency Securities |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 10,066 | 10,775
Available-for-sale marketable securities, Unrealized Gain | 1 |
Available-for-sale marketable securities, Unrealized (Loss) | (58) | (49)
Available-for-sale marketable securities, Fair Market Value | 10,009 | 10,726
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 7,034 | 10,726
Debt Mutual Funds |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 2,878 |
Available-for-sale marketable securities, Unrealized (Loss) | (68) |
Available-for-sale marketable securities, Fair Market Value | 2,810 |
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 1,681 |
Equity and Debt Mutual Funds |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost |  | 19,403
Available-for-sale marketable securities, Unrealized Gain |  | 4,102
Available-for-sale marketable securities, Unrealized (Loss) |  | (75)
Available-for-sale marketable securities, Fair Market Value |  | 23,430
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses |  | 1,723
Certificates of Deposit and Time Deposits |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 1,318 | 167,523
Available-for-sale marketable securities, Unrealized Gain |  | 6
Available-for-sale marketable securities, Unrealized (Loss) |  | (187)
Available-for-sale marketable securities, Fair Market Value | 1,318 | 167,342
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses |  | 138,340
Non-U.S. Government Securities |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 552 | 582
Available-for-sale marketable securities, Unrealized Gain |  | 4
Available-for-sale marketable securities, Unrealized (Loss) | (1) |
Available-for-sale marketable securities, Fair Market Value | 551 | $ 586
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | $ 179 |

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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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