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Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Sep. 27, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 361,666	$ 211,596
Available-for-sale marketable securities, Unrealized Gain	8,284	4,687
Available-for-sale marketable securities, Unrealized (Loss)	(87)	(262)
Available-for-sale marketable securities, Fair Market Value	369,863	216,021
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	24,431	23,999
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	287,670	137,144
Available-for-sale marketable securities, Unrealized Gain	128	160
Available-for-sale marketable securities, Unrealized (Loss)	(9)	(1)
Available-for-sale marketable securities, Fair Market Value	287,789	137,303
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	18,953	2,922
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	73,996	74,452
Available-for-sale marketable securities, Unrealized Gain	8,156	4,527
Available-for-sale marketable securities, Unrealized (Loss)	(78)	(261)
Available-for-sale marketable securities, Fair Market Value	82,074	78,718
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 5,478	$ 21,077

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- Definition

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

+ References

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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=121645371&loc=d3e27161-111563

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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.

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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.

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