Note 13 - Commitments and Contingencies (Details)

Note 13 - Commitments and Contingencies (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Note 13 - Commitments and Contingencies (Details) [Line Items]
Period of Finite Risk Insurance Policy	25 years
Maximum AllowableCoverageOfInsurancePolicy	$ 39,000,000
Financial Assurance Coverage Amount Under Insurance Policy	38,675,000
Sinking Fund Related to Insurance Policy	15,429,000
Interest Earned on Sinking Fund	958,000pesi_InterestEarnedOnSinkingFund
Interest Income, Other	20,000us-gaap_InterestIncomeOther
Insurers Obligation to Entity on Termination of Contract	100.00%
Financial Assurance Coverage Amount Under Second Insurance Policy	7,800,000
Annual Growth Rate of Financial Assurance Coverage Amount Under Second Insurance Policy	1.50%
Maximum Financial Assurance Coverage Amount Under Second Insurance Policy	8,200,000
Sinking Fund Related to Second Insurance Policy	5,905,000
Interest Earned on Sinking Fund Under Second Insurance Policy	205,000
Period of Finite Second Insurance Policy	4 years
Operating Leases, Rent Expense, Net	1,158,000us-gaap_OperatingLeasesRentExpenseNet	1,381,000us-gaap_OperatingLeasesRentExpenseNet
Minimum [Member]
Note 13 - Commitments and Contingencies (Details) [Line Items]
Renewal Fee for Additional Year Under Second Insurance Policy	41,000
Maximum [Member]
Note 13 - Commitments and Contingencies (Details) [Line Items]
Renewal Fee for Additional Year Under Second Insurance Policy	46,000
Non-cancelable Operating Leases [Member]
Note 13 - Commitments and Contingencies (Details) [Line Items]
Operating Leases, Rent Expense	$ 826,000	$ 913,000

Annual report pursuant to Section 13 and 15(d)

Note 13 - Commitments and Contingencies (Details)