Deferred revenue, period of recognition

No definition available.

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- Definition

Derivative instruments, term of derivative contracts

+ References

No definition available.

+ Details

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Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration

- Definition

More-likely-than-not benefit likelihood percentage being realized upon ultimate settlement with taxing authority resulting from sustainability of tax examination

+ References

No definition available.

+ Details

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Namespace Prefix:	pega_
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Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of license fees

+ References

No definition available.

+ Details

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Namespace Prefix:	pega_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount billed to customers under long-term contracts or programs but not paid as of the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3(c))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 910

-SubTopic 310

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49354-109356

+ Details

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Period Type:	instant

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 59

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=6909708&loc=d3e1043-128460

+ Details

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

- Definition

Additions made to capitalized computer software costs during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The maximum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 35

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15217-109273

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 35

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15300-109273

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 35

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15211-109273

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The average useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

No definition available.

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLifeAverage
Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

The maximum useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

No definition available.

+ Details

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- Definition

The minimum useful life of long lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

No definition available.

+ Details

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Significant Accounting Policies (Details) (USD $)	12 Months Ended
Significant Accounting Policies (Details) (USD $)	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009
Significant Accounting Policies [Line Items]
Intangible assets, useful life minimum, years	4
Intangible assets, useful life maximum, years	9
Acquisition-related costs	482,000	$ 5,924,000
More-likely-than-not benefit likelihood percentage being realized upon ultimate settlement with taxing authority resulting from sustainability of tax examination	50.00%
Forward Foreign Currency Contracts [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Term of derivative contracts (in days)	60
Software License [Member]
Significant Accounting Policies [Line Items]
Installment receivables	1,300,000
Software License [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Term of license fees, years	3
Software License [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Term of license fees, years	5
Maintenance Revenues [Member]
Significant Accounting Policies [Line Items]
Deferred revenue, period of recognition	one year
Professional Services Revenues [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Deferred revenue, period of recognition	four months
Equipment [Member]
Significant Accounting Policies [Line Items]
Property and equipment, average useful life, years	3
Furniture And Fixtures [Member]
Significant Accounting Policies [Line Items]
Property and equipment, average useful life, years	5
Capitalized Computer Software [Member]
Significant Accounting Policies [Line Items]
Property and equipment, useful life minimum, years	3
Property and equipment, useful life maximum, years	5
Computer software capitalized during period		700,000	500,000
Chordiant Software, Inc. [Member]
Significant Accounting Policies [Line Items]
Acquisition-related costs	500,000	5,900,000
Chordiant Software, Inc. [Member] \| Diligence Costs And Advisory And Legal Transaction Fees [Member]
Significant Accounting Policies [Line Items]
Acquisition-related costs		3,100,000
Chordiant Software, Inc. [Member] \| Valuation And Tax Consulting Fees [Member]
Significant Accounting Policies [Line Items]
Acquisition-related costs		800,000
Chordiant Software, Inc. [Member] \| Legal Costs [Member]
Significant Accounting Policies [Line Items]
Acquisition-related costs		1,600,000
Chordiant Software, Inc. [Member] \| Integration And Other [Member]
Significant Accounting Policies [Line Items]
Acquisition-related costs		$ 400,000