Employee Stock Purchase Plan, Purchase Price of Shares

No definition available.

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

- Definition

The highest dollar amount from their salary that an employee is permitted to utilize with respect to the plan.

+ References

No definition available.

+ Details

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

- Definition

Minimum percentage of common stock price to grant date price of stock options to trigger vesting.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The expected attainment percentage for the awards based upon forecasted sales and operating income.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of outstanding stock options expected to vest over the remaining vesting period.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Threshold period of specified consecutive trading days within which common stock price to grant date price of options must exceed threshold percentage for a specified number of trading days to vesting, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Number of vesting tranches for share based compensation awards with share-price and service vesting requirements.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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

- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptions
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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

- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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

- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

+ Details

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

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

+ Details

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

- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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

- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

+ Details

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Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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Stock-Based Compensation Plans - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016 USD ($) Tranche $ / shares shares	Mar. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP \| shares	50,876	46,651
Incentive plan, percentage of options expected to vest over the vesting period	93.10%
Incentive plan, weighted-average grant date fair value of stock options granted \| $ / shares	$ 5.54	$ 6.49
Incentive plan, total intrinsic value of stock options exercised	$ 200,000	$ 6,400,000
Expected dividend yield	0.00%
Dividend paid \| $ / shares	$ 0
Number of tranches \| Tranche	3
Stock-based compensation expenses	$ 9,492,000	3,936,000
Stock-based compensation expenses tax benefits	3,600,000	1,500,000
Proceeds from exercises of stock options	237,000	6,918,000
Actual tax benefit realized from tax deductions of option exercises	$ 100,000	$ 2,400,000
Employee Stock Purchase Plan 1999 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance \| shares	4,500,000
Permitted designation for purchase of common stock under ESPP	Participating employees are permitted to designate up to the lesser of $25,000 or 10% of their annual base compensation for the purchase of common stock under the ESPP. Purchases under the ESPP are made one calendar month after the end of each fiscal quarter.
Employee participating annual base compensation designated for purchase of common stock, amount	$ 25,000
Employee participating annual base compensation designated for purchase of common stock, percent	10.00%
Price of common stock purchased under ESPP, description	The price for shares of common stock purchased under the ESPP is 85% of the stock's fair market value on the last business day of the three-month participation period.
Price of common stock purchased under ESPP, percent	85.00%
Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares	$ 7.46
Share-based compensation, trading price percentage	133.00%
Consecutive trading days	20 days
Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares	$ 7.06
Share-based compensation, trading price percentage	167.00%
Consecutive trading days	20 days
Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares	$ 6.50
Share-based compensation, trading price percentage	200.00%
Consecutive trading days	20 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expenses	$ 19,000,000
Unrecognized compensation expenses, weighted-average recognition periods	2 years 6 months
Restricted share awards (RSAs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation awards, shares vested \| shares	5,638
Shares withheld to pay employees' portion of minimum payroll withholding taxes \| shares	2,039
Nonvested shares \| shares	142,868		149,262
Nonvested shares, grant date fair value \| $ / shares	$ 22.71		$ 22.62
Unrecognized compensation expenses	$ 1,100,000
Unrecognized compensation expenses, weighted-average recognition periods	1 year 3 months 18 days
Performance-Based Restricted Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares \| shares	899,958		938,863
Nonvested shares, grant date fair value \| $ / shares	$ 23.42		$ 23.42
Unrecognized compensation expenses	$ 10,500,000
Unrecognized compensation expenses, weighted-average recognition periods	1 year 3 months 18 days
Performance-Based Restricted Share Awards [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected attainment level for the awards granted, percentage	100.00%
Performance-Based Restricted Share Awards [Member] \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected attainment level for the awards granted, percentage	91.00%
Retention RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares \| shares	464,169		0
Nonvested shares, grant date fair value \| $ / shares	$ 17.89		$ 0.00
Unrecognized compensation expenses	$ 6,500,000
Unrecognized compensation expenses, weighted-average recognition periods	10 months 24 days
Retention RSAs [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year 3 months 18 days
Retention RSAs [Member] \| Executive Officers [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year	50.00%
Retention RSAs [Member] \| Executive Officers [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year	50.00%
Retention RSAs [Member] \| Employees other than Named Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	9 months 18 days
Retention RSAs [Member] \| Employees other than Named Executive Officers [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year	50.00%
Retention RSAs [Member] \| Employees other than Named Executive Officers [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year	50.00%
PAY.ON RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares \| shares	476,750		476,750
Nonvested shares, grant date fair value \| $ / shares	$ 23.60		$ 23.60
LTIP Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares \| shares	1,904,027		889,295
Nonvested shares, grant date fair value \| $ / shares	$ 18.44		$ 19.13
Unrecognized compensation expenses	$ 26,300,000
Unrecognized compensation expenses, weighted-average recognition periods	2 years 8 months 12 days