General form of registration statement for all companies including face-amount certificate companies

Property and Equipment, Net - Property and Equipment Accumulated Depreciation (Detail)

v2.4.1.9
Property and Equipment, Net - Property and Equipment Accumulated Depreciation (Detail) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Property, Plant and Equipment [Line Items]    
Accumulated depreciation $ 2,182,773us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment $ 2,103,175us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Leasehold Improvements [Member]    
Property, Plant and Equipment [Line Items]    
Accumulated depreciation 41,606us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember
37,904us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember
Laboratory Equipment [Member]    
Property, Plant and Equipment [Line Items]    
Accumulated depreciation 1,886,807us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pirs_LaboratoryEquipmentMember
1,845,098us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= pirs_LaboratoryEquipmentMember
Office and Computer Equipment [Member]    
Property, Plant and Equipment [Line Items]    
Accumulated depreciation $ 254,360us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_MachineryAndEquipmentMember
$ 220,172us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_MachineryAndEquipmentMember