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Intangible Assets, Net - Additional Information (Detail) | 9 Months Ended
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Sep. 30, 2017 USD ($)
Intangible Liability Disclosure [Abstract] |
Impairment of intangible asset | $ 0

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- Definition Intangible Liability Disclosure [Abstract] + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 + Details
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Balance Type: | debit
Period Type: | duration