Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 1,304,711	$ 745,498
Available-for-sale marketable securities, Unrealized Gain	2,977	2,145
Available-for-sale marketable securities, Unrealized (Loss)	(2,821)	(4,019)
Available-for-sale marketable securities, Fair Market Value	1,304,867	743,624
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	732,979	601,660
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	871,321	478,306
Available-for-sale marketable securities, Unrealized Gain	134	38
Available-for-sale marketable securities, Unrealized (Loss)	(431)	(648)
Available-for-sale marketable securities, Fair Market Value	871,024	477,696
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	423,128	374,785
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	433,390	267,192
Available-for-sale marketable securities, Unrealized Gain	2,843	2,107
Available-for-sale marketable securities, Unrealized (Loss)	(2,390)	(3,371)
Available-for-sale marketable securities, Fair Market Value	433,843	265,928
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 309,851	$ 226,875

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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