Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 211,596	$ 259,011
Available-for-sale marketable securities, Unrealized Gain	4,687	592
Available-for-sale marketable securities, Unrealized (Loss)	(262)	(2,967)
Available-for-sale marketable securities, Fair Market Value	216,021	256,636
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	23,999	191,978
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	137,144	190,100
Available-for-sale marketable securities, Unrealized Gain	160	88
Available-for-sale marketable securities, Unrealized (Loss)	(1)	(92)
Available-for-sale marketable securities, Fair Market Value	137,303	190,096
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	2,922	140,262
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	74,452	68,911
Available-for-sale marketable securities, Unrealized Gain	4,527	504
Available-for-sale marketable securities, Unrealized (Loss)	(261)	(2,875)
Available-for-sale marketable securities, Fair Market Value	78,718	66,540
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 21,077	$ 51,716

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=118939692&loc=d3e27161-111563

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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.

+ 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

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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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