v2.4.0.8

Fair Value Measurements of Financial Assets and Liabilities - Additional Information (Detail) (USD $) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 Short-term Investments | Dec. 31, 2013 Short-term Investments
Impairment charge | $ 66,000 | $ 155,000 | $ 0 | $ 0
Maturity period of short term investments | Beyond 90 days |  |  |
Stated maturity period of short term investments | One year or more |  |  |

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- Definition Maturity period of short term investments. + References No definition available. + Details
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- Definition Stated maturity period of short term investments. + References No definition available. + Details
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- Definition The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230 + Details
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