Employee Stock Purchase Plan, Purchase Price of Shares

No definition available.

Name:	aciw_EmployeeStockPurchasePlanPurchasePriceOfShares
Namespace Prefix:	aciw_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Reversal of previously recognized expense due to a performance share based award previously deemed probable of vesting being determined not probable in the current period.

+ References

No definition available.

+ Details

Name:	aciw_ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCostReversal
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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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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Namespace Prefix:	aciw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The maximum percentage that can be achieved under the predetermined performance thresholds for the performance based restricted share awards.

+ 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 LTIP Performance Shares based upon forecasted sales and operating income.

+ References

No definition available.

+ Details

Name:	aciw_ShareBasedCompensationArrangementsPerformanceSharesExpectedAttainment
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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

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

- Definition

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

+ References

No definition available.

+ Details

Name:	aciw_ShareBasedCompensationVestingTranches
Namespace Prefix:	aciw_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The attainment percentage expected to vest for the defined awards.

+ References

No definition available.

+ Details

Name:	aciw_TargetAttainmentPercentageExpectedToVest
Namespace Prefix:	aciw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_CommonStockDividendsPerShareCashPaid
Namespace Prefix:	us-gaap_
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
Namespace Prefix:	us-gaap_
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

Name:	us-gaap_ProceedsFromStockOptionsExercised
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

Name:	us-gaap_ShareBasedCompensation
Namespace Prefix:	us-gaap_
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

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
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

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

- 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
Namespace Prefix:	us-gaap_
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

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
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

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
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

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue
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

- Details

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- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
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Data Type:	na
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Period Type:

- 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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Stock-Based Compensation Plans - Additional Information (Detail)		3 Months Ended		9 Months Ended
	Sep. 15, 2015	Sep. 30, 2015 USD ($) Tranche shares	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) Tranche $ / shares shares	Sep. 30, 2014 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP \| shares				123,866	109,825
Incentive plan, percentage of options expected to vest over the vesting period		93.10%		93.10%
Incentive plan, weighted-average grant date fair value of stock options granted \| $ / shares				$ 6.49	$ 9.02
Incentive plan, total intrinsic value of stock options exercised				$ 12,100,000	$ 15,300,000
Dividend yield				0.00%
Dividend paid \| $ / shares				$ 0
Number of tranches \| Tranche		3		3
Stock-based compensation expenses		$ 800,000	$ 4,600,000	$ 10,050,000	13,742,000
Stock-based compensation expenses tax benefits		300,000	$ 1,700,000	3,800,000	5,200,000
Proceeds from exercises of stock options				11,554,000	11,106,000
Actual tax benefit realized from tax deductions of option exercises				$ 4,600,000	$ 5,800,000
Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vested grant date fair value \| $ / shares				$ 8.01
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				$ 7.56
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				$ 7.00
Share-based compensation, trading price percentage				200.00%
Consecutive trading days				20 days
Restricted share awards (RSAs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation awards, shares vested \| shares				158,217
Shares withheld to pay employees' portion of minimum payroll withholding taxes \| shares				24,983
Unrecognized compensation costs		2,300,000		$ 2,300,000
Unrecognized compensation costs, weighted-average recognition periods				1 year 4 months 24 days
Performance-Based Restricted Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year 3 months 18 days
Unrecognized compensation costs		18,000,000		$ 18,000,000
Unrecognized compensation costs, weighted-average recognition periods				1 year 7 months 6 days
Performance-Based Restricted Share Awards [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				3 years
Award vesting percentage for each year				33.00%
Threshold level percentage for share awards				150.00%
Award grants assuming percentage				100.00%
Performance-Based Restricted Share Awards [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year				33.00%
Performance-Based Restricted Share Awards [Member] \| Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage for each year				33.00%
2012 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected attainment level for the awards granted, percentage				0.00%
Stock Based Compensation Plans Twenty Fifteen Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected attainment level for the awards granted, percentage				100.00%
Maximum [Member] \| 2013 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected attainment level for the awards granted, percentage				75.00%
Minimum [Member] \| 2013 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected attainment level for the awards granted, percentage				0.00%
Share based compensation expense reversal		5,600,000		$ 5,600,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs		$ 11,400,000		$ 11,400,000
Unrecognized compensation costs, weighted-average recognition periods				2 years 1 month 6 days
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		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		$ 25,000
Employee participating annual base compensation designated for purchase of common stock, percent		10.00%		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%
LTIP Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation awards, shares vested \| shares				548,671
Shares withheld to pay employees' portion of minimum payroll withholding taxes \| shares				196,169
Unrecognized compensation costs		$ 12,500,000		$ 12,500,000
Unrecognized compensation costs, weighted-average recognition periods				2 years 7 months 6 days