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Realized and Net Change in Unrealized Gains (Losses) on Investments (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Gain (Loss) on Investments [Line Items] |  |  |  |
Realized Gains (Losses) on other investments | $ 1,282 | $ (460) | $ 1,274 | $ 5,152
Net Change in Unrealized Gains (Losses) on other investments | (2,779) | 239 | (3,233) | (6,252)
Total realized and net change in unrealized gains (losses) on other investments | $ (1,497) | $ (221) | $ (1,959) | $ (1,100)

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- Definition The difference between the book value and the sale price of other nonspecific investments. This element is used when other, more specific, elements are not appropriate. This element refers to the gain (loss) included in earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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