Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 334,077	$ 601,976
Available-for-sale marketable securities, Unrealized Gain	5,477	9,077
Available-for-sale marketable securities, Unrealized (Loss)	(718)	(213)
Available-for-sale marketable securities, Fair Market Value	338,836	610,840
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	91,937	70,418
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	244,213	522,228
Available-for-sale marketable securities, Unrealized Gain	64	92
Available-for-sale marketable securities, Unrealized (Loss)	(46)	(40)
Available-for-sale marketable securities, Fair Market Value	244,231	522,280
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	54,798	61,806
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	89,864	79,748
Available-for-sale marketable securities, Unrealized Gain	5,413	8,985
Available-for-sale marketable securities, Unrealized (Loss)	(672)	(173)
Available-for-sale marketable securities, Fair Market Value	94,605	88,560
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 37,139	$ 8,612

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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