Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The average effective interest rate during the reporting period.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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-Publisher FASB
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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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Period Type:

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=csgs_TwoThousandSixteenSeniorConvertibleNotesMember
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Debt - Long-Term Debt (Parenthetical) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Sep. 30, 2021	Mar. 31, 2016
2021 Credit Agreement
Debt Instrument [Line Items]
Revolving loan facility		$ 600,000,000.0
2021 Credit Agreement \| 2021 Term Loan
Debt Instrument [Line Items]
Basis spread on term loan	1.625%
Term loan combined interest rate	6.355%
Maturity period	Sep. 30, 2026
2021 Credit Agreement \| Revolving Loan
Debt Instrument [Line Items]
Term loan combined interest rate	6.355%
Maturity period	Sep. 30, 2026
Revolving loan facility	$ 450,000,000	450,000,000.0
2018 Credit Agreement
Debt Instrument [Line Items]
Revolving loan facility		$ 350,000,000.0
Senior Convertible Notes 2016
Debt Instrument [Line Items]
Maturity period	Mar. 15, 2036
Interest rate on senior convertible notes	4.25%		4.25%