Annual report pursuant to Section 13 and 15(d)

2. Summary of Significant Accounting Policies (Details 4)

v2.4.1.9
2. Summary of Significant Accounting Policies (Details 4)
12 Months Ended
Dec. 31, 2014
Non-Employee Board Members  
Expected life 6 years
Expected volatility Minimum 134.75%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum
/ us-gaap_PlanNameAxis
= pbio_NonEmployeeBoardMembersMember
Expected volatility Maximum 141.15%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum
/ us-gaap_PlanNameAxis
= pbio_NonEmployeeBoardMembersMember
Risk-free interest rate Minimum 1.90%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum
/ us-gaap_PlanNameAxis
= pbio_NonEmployeeBoardMembersMember
Risk-free interest rate Maximum 2.54%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum
/ us-gaap_PlanNameAxis
= pbio_NonEmployeeBoardMembersMember
Forfeiture rate 5.00%pbio_ShareBasedCompensationRateOfForfeiture
/ us-gaap_PlanNameAxis
= pbio_NonEmployeeBoardMembersMember
Expected dividend yield 0.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
/ us-gaap_PlanNameAxis
= pbio_NonEmployeeBoardMembersMember
CEO, other Officers and Employees  
Expected life 6 years
Expected volatility Minimum 132.20%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum
/ us-gaap_PlanNameAxis
= pbio_EmployeesOfficersMember
Expected volatility Maximum 141.15%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum
/ us-gaap_PlanNameAxis
= pbio_EmployeesOfficersMember
Risk-free interest rate Minimum 1.09%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum
/ us-gaap_PlanNameAxis
= pbio_EmployeesOfficersMember
Risk-free interest rate Maximum 2.54%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum
/ us-gaap_PlanNameAxis
= pbio_EmployeesOfficersMember
Forfeiture rate 5.00%pbio_ShareBasedCompensationRateOfForfeiture
/ us-gaap_PlanNameAxis
= pbio_EmployeesOfficersMember
Expected dividend yield 0.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
/ us-gaap_PlanNameAxis
= pbio_EmployeesOfficersMember