Quarterly report pursuant to Section 13 or 15(d)

Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details)

v2.4.1.9
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) (USD $)
3 Months Ended 0 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Jul. 25, 2011
Dec. 31, 2014
Dec. 31, 2013
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) [Line Items]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 222,766us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber [1] 340,800us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber [1]   239,023us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber 362,800us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number 213,966us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber 340,800us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in Dollars per share) $ 7.89us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice [1] $ 9.62us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice [1]   $ 7.81us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice $ 9.53us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term 5 years [1] 2 years 255 days [1]      
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit (in Dollars per share) $ 2.79us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit $ 2.79us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit      
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit (in Dollars per share) $ 14.75us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit $ 14.75us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit      
Reduction in Stock Based Compensation Expense (in Dollars)   $ 54,000pesi_ReductionInStockBasedCompensationExpense      
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) $ 0us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice $ 0us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars) 112,000us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized        
Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Remaining Fiscal Year (in Dollars) 40,000pesi_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedRemainingFiscalYear        
Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized, Next Twelve Months (in Dollars) 53,000pesi_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedNextTwelveMonths        
Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized In Year Two (in Dollars) $ 19,000pesi_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedInYearTwo        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period 1,257us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised 0us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised      
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share) $ 2.79us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice $ 0us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice      
Employee Stock Option [Member] | Contractual Term with One-third Yearly Vesting [Member] | Chief Operating Officer [Member] | The 2010 Stock Option Plan [Member]          
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) [Line Items]          
Share Based Compensation Maximum Contractual Term     6 years    
Employee Stock Option [Member] | The 2010 Stock Option Plan [Member]          
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) [Line Items]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 55,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
/ us-gaap_PlanNameAxis
= pesi_The2010StockOptionPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
/ us-gaap_PlanNameAxis
= pesi_The2010StockOptionPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in Dollars per share) $ 5.00us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
/ us-gaap_PlanNameAxis
= pesi_The2010StockOptionPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term 5 years 109 days        
Director Stock Options [Member] | The 2003 Outside Directors Stock Plan [Member]          
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) [Line Items]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 167,766us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
/ us-gaap_AwardTypeAxis
= pesi_DirectorStockOptionsMember
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number 167,766us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber
/ us-gaap_AwardTypeAxis
= pesi_DirectorStockOptionsMember
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in Dollars per share) $ 8.84us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
/ us-gaap_AwardTypeAxis
= pesi_DirectorStockOptionsMember
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term 4 years 328 days        
Chief Operating Officer [Member] | The 2010 Stock Option Plan [Member]          
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) [Line Items]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross     60,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
/ us-gaap_PlanNameAxis
= pesi_The2010StockOptionPlanMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_ChiefOperatingOfficerMember
   
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share)     7.85us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
/ us-gaap_PlanNameAxis
= pesi_The2010StockOptionPlanMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_ChiefOperatingOfficerMember
   
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period     3 years    
The 2003 Outside Directors Stock Plan [Member]          
Note 4 - Capital Stock, Stock Plans and Stock Based Compensation (Details) [Line Items]          
Stock Issued During Period, Shares, Share-based Compensation, Gross 16,075us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period 1,257us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures 1,257us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share) $ 2.79us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice
/ us-gaap_PlanNameAxis
= pesi_The2003OutsideDirectorsStockPlanMember
       
[1] Options with exercise prices ranging from $2.79 to $14.75