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

Related Party Interest Expenses (Detail)

v2.4.1.9
Related Party Interest Expenses (Detail) (USD $)
 9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Schedule of Other Related Party Transactions [Line Items]    
Related party interest Expense $ 204,110us-gaap_InterestExpenseRelatedParty $ 186,044us-gaap_InterestExpenseRelatedParty
Orbimed Private Investments III, LP    
Schedule of Other Related Party Transactions [Line Items]    
Related party interest Expense 63,955us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_OrbimedPrivateInvestmentsIiiLpMember 		58,351us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_OrbimedPrivateInvestmentsIiiLpMember
Global Life Science Ventures Fund    
Schedule of Other Related Party Transactions [Line Items]    
Related party interest Expense 57,709us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_GlobalLifeScienceVenturesFundMember 		51,778us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_GlobalLifeScienceVenturesFundMember
Gilde Europe Food & Agribusiness Fund B.V    
Schedule of Other Related Party Transactions [Line Items]    
Related party interest Expense 54,158us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_GildeEuropeFoodAgribusinessFundMember 		49,921us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_GildeEuropeFoodAgribusinessFundMember
Forbion B.V    
Schedule of Other Related Party Transactions [Line Items]    
Related party interest Expense $ 28,288us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_ForbionMember 		$ 25,994us-gaap_InterestExpenseRelatedParty
/ us-gaap_RelatedPartyTransactionAxis
= pirs_ForbionMember