Annual report pursuant to Section 13 and 15(d)

Revenue - Revenue Received (Detail)

v2.4.1.9
Revenue - Revenue Received (Detail) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Research and Development Arrangement, Contract to Perform for Others [Line Items]    
Revenue from grant $ 830,408us-gaap_RevenueFromGrants $ 2,547,382us-gaap_RevenueFromGrants
Seventh Research Framework Program (FP7 Agreement) [Member]    
Research and Development Arrangement, Contract to Perform for Others [Line Items]    
Amounts received   2,915,559us-gaap_ResearchAndDevelopmentArrangementWithFederalGovernmentCustomerFundingToOffsetCostsIncurred
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember
Revenue from grant $ 714,388us-gaap_RevenueFromGrants
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember
$ 2,430,358us-gaap_RevenueFromGrants
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember