Debt instrument convertible conversion price premium.

No definition available.

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Namespace Prefix:	csgs_
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Balance Type:	na
Period Type:	duration

- Definition

Minimum quarterly dividends to adjust conversion rate.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Purchase of capped call transactions related to 2023 convertible notes.

+ References

No definition available.

+ Details

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

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Period Type:	duration

- Definition

The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

+ Details

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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- Definition

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

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- 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.

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- Definition

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

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- Definition

Start date of debt instrument redemption period, in YYYY-MM-DD format.

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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- 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.

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- Definition

The cash outflow for loan and debt issuance costs.

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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Debt - 2023 Convertible Notes (Details Textual) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($) Tradingday $ / shares shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Purchase of capped call transactions		$ (34,298)	$ 0	$ 0
Deferred income taxes on the premiums paid for the capped call transactions		57,732	26,089
Net financing cost		14,539	0	3,000
Cash payments on revolving loan		327,500	$ 264,801	$ 128,438
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Cash payments on revolving loan		275,000
2023 Convertible Notes
Debt Instrument [Line Items]
Carrying value of debt	$ 425,000
Interest rate on senior convertible notes	3.875%
Maturity period	Sep. 15, 2028
Initial conversion rate of common stock	14.0753
Convertible Notes, initial conversion of Par Value Convertible Notes to common stock	$ 1,000
Initial conversion price \| $ / shares	$ 71.05
Debt instrument, premium percentage	80.00%
Initial conversion rate \| $ / shares	$ 0.28
Redemption period	Sep. 21, 2026
Trading days \| Tradingday	20
Consecutive trading days \| Tradingday	30
Purchase of capped call transactions	$ 34,300
Deferred income taxes on the premiums paid for the capped call transactions	7,900
Net financing cost	14,000
Proceeds from the sale of the 2023 Notes	$ 411,000
2023 Convertible Notes \| Common Stock
Debt Instrument [Line Items]
Number of shares issuable upon conversion \| shares	5,980
Number of common stock repurchased \| shares	1,700
Amount of common stock repurchased	$ 90,100
2023 Convertible Notes \| Minimum
Debt Instrument [Line Items]
Carrying value of debt	$ 100,000
Conversion price	130.00%
2023 Convertible Notes \| Call Option [Member]
Debt Instrument [Line Items]
Initial conversion price \| $ / shares	$ 96.52
2021 Credit Agreement
Debt Instrument [Line Items]
Net financing cost	$ 500	$ 3,000
Credit Agreement					$ 600,000
2021 Credit Agreement \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maturity period		Sep. 30, 2026
Cash payments on revolving loan		$ 275,000
Credit Agreement		$ 450,000			$ 450,000