Long-Lived Assets (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Summary of carrying value of assets
Gross Carrying Amount, Client contracts	$ 135,324	$ 257,485
Client contracts, Accumulated Amortization	(74,137)	(182,182)
Client contracts, Net Amount	61,187	75,303
Gross Carrying Amount, Software	118,205	106,868
Software, Accumulated Amortization	(77,106)	(68,496)
Software, Net Amount	41,099	38,372
Gross Carrying Amount, Total	253,529	364,353
Accumulated Amortization, Total	(151,243)	(250,678)
Net Amount, Total	$ 102,286	$ 113,675

Accumulated amount of amortization of client contract assets.

No definition available.

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Namespace Prefix:	csgs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of client contract assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	csgs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, net of accumulated amortization of: (I) investments in client contracts; (II) direct and incremental costs that have been capitalized related to contractual arrangements where revenues have been deferred to convert or set-up client customers onto outsourced solutions; and (III) assets acquired in a business combination representing a favorable existing relationship with customers.

+ References

No definition available.

+ Details

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Namespace Prefix:	csgs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Accumulated amount of amortization of software assets.

+ References

No definition available.

+ Details

Name:	csgs_SoftwareAccumulatedAmortization
Namespace Prefix:	csgs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of software assets.

+ References

No definition available.

+ Details

Name:	csgs_SoftwareGross
Namespace Prefix:	csgs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, net of accumulated amortization, of (I) software and similar intellectual property rights from various business combinations; and (II) internal use software.

+ References

No definition available.

+ Details

Name:	csgs_SoftwareNet
Namespace Prefix:	csgs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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