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Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Jun. 28, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 305,170	$ 211,596
Available-for-sale marketable securities, Unrealized Gain	8,756	4,687
Available-for-sale marketable securities, Unrealized (Loss)	(151)	(262)
Available-for-sale marketable securities, Fair Market Value	313,775	216,021
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	20,156	23,999
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	229,471	137,144
Available-for-sale marketable securities, Unrealized Gain	331	160
Available-for-sale marketable securities, Unrealized (Loss)	(11)	(1)
Available-for-sale marketable securities, Fair Market Value	229,791	137,303
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	17,366	2,922
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	75,699	74,452
Available-for-sale marketable securities, Unrealized Gain	8,425	4,527
Available-for-sale marketable securities, Unrealized (Loss)	(140)	(261)
Available-for-sale marketable securities, Fair Market Value	83,984	78,718
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 2,790	$ 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=118939692&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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