Percentage of discretionary contributions made by an employer to a defined contribution plan.

No definition available.

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- Definition

Maximum amount matched by the employer, per employee, under a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan, Employer Matching Contribution, Service Period Requirement For Company Match

+ References

No definition available.

+ Details

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- Definition

Schedule Of Defined Contribution Plans Disclosures [Line Items]

+ References

No definition available.

+ Details

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

+ Details

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

Maximum amount the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Employee Benefit Plans (Details) - USD ($)	12 Months Ended
Employee Benefit Plans (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, cost	$ 13,200,000	$ 12,800,000	$ 13,400,000
ACI 401(k) Plan
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, cost	$ 6,200,000	5,000,000.0	6,200,000
Defined contribution plan, maximum annual contribution per employee, percentage	75.00%
Defined contribution plan, employer matching contribution, percentage of match	100.00%
Defined contribution plan, employer matching contribution, percent of eligible participant contributions	4.00%
Defined contribution plan, employer matching contribution, maximum amount per employee	$ 6,000
Defined contribution plan, service period requirement for company match	1 year
ACI 401(k) Plan \| Employees under Age 50
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, maximum annual contribution per employee, amount	$ 23,000
ACI 401(k) Plan \| Employees Aged 50 or Older
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, maximum annual contribution per employee, amount	$ 30,500
ACI 401(k) Plan \| Second Eligible Participant Contributions
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, employer matching contribution, percentage of match	50.00%
ACI 401(k) Plan \| Second Eligible Participant Contributions \| Maximum
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, employer matching contribution, percent of eligible participant contributions	4.00%
ACI Worldwide EMEA Group Personal Pension Scheme
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, cost	$ 1,700,000	$ 1,700,000	$ 1,600,000
ACI Worldwide EMEA Group Personal Pension Scheme \| Employed at December 1, 2000
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, employer discretionary contribution, percentage of eligible compensation	8.50%
ACI Worldwide EMEA Group Personal Pension Scheme \| Employed Subsequent to December 1, 2000 \| Minimum
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, employer discretionary contribution, percentage of eligible compensation	7.00%
ACI Worldwide EMEA Group Personal Pension Scheme \| Employed Subsequent to December 1, 2000 \| Maximum
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Defined contribution plan, employer discretionary contribution, percentage of eligible compensation	10.00%