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Long-term Investment - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | 36 Months Ended | 48 Months Ended
--- | --- | --- | --- | ---
Feb. 28, 2007 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2009 | Dec. 31, 2010 | Dec. 31, 2014
Schedule of Cost-method Investments [Line Items] |  |  |  |  |  |  |
Cost method investment impairments other than temporary |  | $ 0 | $ 0 | $ 0 |  |  |
Vastview Technology, Corp. (Vastview) |  |  |  |  |  |  |
Schedule of Cost-method Investments [Line Items] |  |  |  |  |  |  |
Invested in common stock | $ 3,360 |  |  |  |  |  |
Cost method investment capital return |  |  |  | $ 46 | $ 808 |  |
Recognized an impairment charges |  |  |  |  |  | $ 2,462 | $ 0

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- Definition This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph c, d -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 + Details
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