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Acquisitions - Summary of Allocation of Consideration to Fair Value of Tangible and Intangible Assets Acquired and Liabilities Assumed (Detail) (USD $)
In Thousands, unless otherwise specified
0 Months Ended
Feb. 07, 2014
Jan. 30, 2014
Dec. 31, 2014
Dec. 31, 2013
Business Acquisition [Line Items]        
Goodwill     $ 34,972us-gaap_Goodwill $ 0us-gaap_Goodwill
Skyfence Networks Ltd. [Member]        
Business Acquisition [Line Items]        
Net tangible assets 1,014us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
/ us-gaap_BusinessAcquisitionAxis
= impv_SkyfenceNetworksLtdMember
     
Intangible assets 7,965us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill
/ us-gaap_BusinessAcquisitionAxis
= impv_SkyfenceNetworksLtdMember
     
Deferred tax liability assumed (1,528)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent
/ us-gaap_BusinessAcquisitionAxis
= impv_SkyfenceNetworksLtdMember
     
Goodwill 29,473us-gaap_Goodwill
/ us-gaap_BusinessAcquisitionAxis
= impv_SkyfenceNetworksLtdMember
     
Total purchase price 36,924us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= impv_SkyfenceNetworksLtdMember
     
Tomium Software, LLC. [Member]        
Business Acquisition [Line Items]        
Intangible assets   2,704us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill
/ us-gaap_BusinessAcquisitionAxis
= impv_TomiumSoftwareLlcMember
   
Goodwill   5,499us-gaap_Goodwill
/ us-gaap_BusinessAcquisitionAxis
= impv_TomiumSoftwareLlcMember
   
Total intangible assets acquired   8,203impv_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedGoodwillAndIntangibleAssets
/ us-gaap_BusinessAcquisitionAxis
= impv_TomiumSoftwareLlcMember
   
Other acquired tangible assets   60us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets
/ us-gaap_BusinessAcquisitionAxis
= impv_TomiumSoftwareLlcMember
   
Total purchase price   $ 8,263us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= impv_TomiumSoftwareLlcMember