v2.4.1.9

401(K) Plan - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2014
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract] |
Defined contribution plan, employer contribution | $ 0us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount

X
- Details
Name: | us-gaap_DefinedContributionPensionAndOtherPostretirementPlansDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration