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Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands | Apr. 01, 2018 | Dec. 31, 2017
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Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | $ 929,385 | $ 1,470,729
Available-for-sale marketable securities, Unrealized Gain | 1,240 | 6,582
Available-for-sale marketable securities, Unrealized (Loss) | (3,453) | (3,406)
Available-for-sale marketable securities, Fair Market Value | 927,172 | 1,473,905
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 890,956 | 1,350,896
Marketable securities |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 861,794 | 1,349,970
Available-for-sale marketable securities, Unrealized Gain | 54 | 38
Available-for-sale marketable securities, Unrealized (Loss) | (1,322) | (2,029)
Available-for-sale marketable securities, Fair Market Value | 860,526 | 1,347,979
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 847,446 | 1,288,844
Long-term marketable securities |  |
Schedule of Available-for-sale Securities |  |
Available-for-sale marketable securities, Cost | 67,591 | 120,759
Available-for-sale marketable securities, Unrealized Gain | 1,186 | 6,544
Available-for-sale marketable securities, Unrealized (Loss) | (2,131) | (1,377)
Available-for-sale marketable securities, Fair Market Value | 66,646 | 125,926
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | $ 43,510 | $ 62,052

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562 + Details
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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://www.xbrl.org/2003/role/presentationRef -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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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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