Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Mar. 29, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 286,073	$ 211,596
Available-for-sale marketable securities, Unrealized Gain	6,164	4,687
Available-for-sale marketable securities, Unrealized (Loss)	(1,187)	(262)
Available-for-sale marketable securities, Fair Market Value	291,050	216,021
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	42,283	23,999
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	210,722	137,144
Available-for-sale marketable securities, Unrealized Gain	430	160
Available-for-sale marketable securities, Unrealized (Loss)	(151)	(1)
Available-for-sale marketable securities, Fair Market Value	211,001	137,303
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	32,037	2,922
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	75,351	74,452
Available-for-sale marketable securities, Unrealized Gain	5,734	4,527
Available-for-sale marketable securities, Unrealized (Loss)	(1,036)	(261)
Available-for-sale marketable securities, Fair Market Value	80,049	78,718
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 10,246	$ 21,077

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

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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

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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

No definition available.

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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

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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.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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