Quarterly report pursuant to Section 13 or 15(d)

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Notes Details

Note 3 - Intangible Assets (Details) - Other Intangible Assets

v2.4.1.9

Note 3 - Intangible Assets (Details) - Other Intangible Assets (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,809	$ 4,802
Accumulated Amortization	(2,267)	(2,140)
Net Carrying Amount	2,542	2,662
Patents [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Lives (Years)	8 years
Patents [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Lives (Years)	18 years
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	512	512
Accumulated Amortization	(177)	(168)
Net Carrying Amount	335	344
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Lives (Years)	3 years
Gross Carrying Amount	382	375
Accumulated Amortization	(339)	(319)
Net Carrying Amount	43	56
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Lives (Years)	12 years
Gross Carrying Amount	3,370	3,370
Accumulated Amortization	(1,419)	(1,335)
Net Carrying Amount	1,951	2,035
Permits [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Lives (Years)	10 years
Gross Carrying Amount	545	545
Accumulated Amortization	(332)	(318)
Net Carrying Amount	$ 213	$ 227

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=pesi_PermitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_ComputerSoftwareIntangibleAssetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_PatentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: