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Stock-Based Compensation - Schedule of Employee Stock Purchase Plan (Detail) (USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]    
Shares purchased under ESPP 23,713us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward 17,670us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward
Average price of shares purchased under ESPP $ 8.00us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased  
Intrinsic value of shares purchased under ESPP $ 33,000immr_ShareBasedCompensationArrangementByShareBasedPaymentAwardIntrinsicValueOfSharesPurchasedForAward