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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 | 0 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross |  | 0 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 222,766 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber | [1] | 340,800 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber | [1] |  | 239,023 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber | 362,800 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number | 213,966 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber |  | 340,800 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in Dollars per share) | $ 7.89 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice | [1] | $ 9.62 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice | [1] |  | $ 7.81 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice | $ 9.53 us-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) | $ 2.79 us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit |  | $ 2.79 us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit |  |  |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit (in Dollars per share) | $ 14.75 us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit |  | $ 14.75 us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit |  |  |  |
Reduction in Stock Based Compensation Expense (in Dollars) |  |  | $ 54,000 pesi_ReductionInStockBasedCompensationExpense |  |  |  |
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ 0 us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice |  | $ 0 us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice |  |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars) | 112,000 us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized |  |  |  |  |  |
Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Remaining Fiscal Year (in Dollars) | 40,000 pesi_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedRemainingFiscalYear |  |  |  |  |  |
Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized, Next Twelve Months (in Dollars) | 53,000 pesi_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedNextTwelveMonths |  |  |  |  |  |
Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized In Year Two (in Dollars) | $ 19,000 pesi_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedInYearTwo |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | 1,257 us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised |  | 0 us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised |  |  |  |
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share) | $ 2.79 us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice |  | $ 0 us-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 | 55,000 us-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 | 0 us-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) | $ 5.00 us-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 | 167,766 us-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 | 167,766 us-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) | $ 8.84 us-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 |  |  |  |  | 60,000 us-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) |  |  |  |  | 7.85 us-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 | 16,075 us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross / us-gaap_PlanNameAxis = pesi_The2003OutsideDirectorsStockPlanMember |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | 1,257 us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised / us-gaap_PlanNameAxis = pesi_The2003OutsideDirectorsStockPlanMember |  |  |  |  |  |
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures | 1,257 us-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) | $ 2.79 us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice / us-gaap_PlanNameAxis = pesi_The2003OutsideDirectorsStockPlanMember |  |  |  |  |  |
[1] | Options with exercise prices ranging from $2.79 to $14.75

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