Investments - Debt, Equity and Other Securities - Summary of the Company's Investments in Debt, Equity and Other Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Investments Debt And Equity Securities [Abstract]
Marketable trading securities	$ 37,787
Marketable available-for-sale securities	378	$ 395
Cost method investments	7,474	32,516
Total	$ 7,852	$ 32,911

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
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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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