Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Apr. 01, 2018	Dec. 31, 2017
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

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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