Annual report pursuant to Section 13 and 15(d)

Revenue - Balance Sheet Items Related to FP7 Agreement (Detail)

v2.4.1.9
Revenue - Balance Sheet Items Related to FP7 Agreement (Detail) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Research and Development Arrangement, Contract to Perform for Others [Line Items]    
Other current assets (receivables from FP7 grant) $ 1,207,072us-gaap_OtherAssetsCurrent $ 449,733us-gaap_OtherAssetsCurrent
Cash (restricted cash) 0us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue 72,497us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
Deferred revenue   544,562us-gaap_DeferredRevenueCurrent
Seventh Research Framework Program (FP7 Agreement) [Member]    
Research and Development Arrangement, Contract to Perform for Others [Line Items]    
Other current assets (receivables from FP7 grant) 857,489us-gaap_OtherAssetsCurrent
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember
261,568us-gaap_OtherAssetsCurrent
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember
Cash (restricted cash)   72,497us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember
Deferred revenue   $ 69,444us-gaap_DeferredRevenueCurrent
/ us-gaap_ProductOrServiceAxis
= pirs_SeventhResearchFrameworkProgramMember