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

No definition available.

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- Definition

Debt Instrument Interest Additional Interest Above Federal Fund Rate

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Interest Additional Interest Above One Month LIBOR Rate

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument Issue Price Percentage Of Principal Amount

+ References

No definition available.

+ Details

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

- Definition

Percentage of capital stock pledged as collateral under the Company's Credit Agreement.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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

- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, 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
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Period Type:	duration

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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

- 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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

+ Details

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Period Type:	duration

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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Debt - Additional Information (Detail) - USD ($)		3 Months Ended
Debt - Additional Information (Detail) - USD ($)	Feb. 24, 2017	Mar. 31, 2018	Mar. 31, 2017	Aug. 20, 2013
Debt Instrument [Line Items]
Proceeds from revolving credit facility		$ 48,000,000	$ 12,000,000
Proceeds from term portion of credit agreement			$ 415,000,000
Credit facility, interest rate description		The applicable margin for borrowings under the Credit Facility is, based on the calculation of the applicable consolidated total leverage ratio, between 0.25% to 1.25% with respect to base rate borrowings and between 1.25% and 2.25% with respect to LIBOR rate borrowings. Interest is due and payable monthly. The interest rate in effect at March 31, 2018 for the Credit Facility was 3.63%.
Credit facility, interest rate margin above federal fund rate		0.50%
Credit facility, interest rate margin above one-month LIBOR rate		1.00%
Credit facility, borrowing rate		3.63%
Credit Facility maturity date		Feb. 24, 2022
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Unused borrowings		$ 500,000,000
Term Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility amount outstanding		389,100,000
Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes amount outstanding		$ 300,000,000		$ 300,000,000
Issue price percentage of senior notes of the principal amount				100.00%
Percentage of interest rate on notes				6.375%
Maturity date of senior notes		Aug. 15, 2020
Credit Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Credit facility, interest rate margin above base rate		0.25%
Credit facility, interest rate margin above LIBOR rate		1.25%
Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Credit facility, interest rate margin above base rate		1.25%
Credit facility, interest rate margin above LIBOR rate		2.25%
Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity	$ 500,000,000
Credit facilities, maturity	5 years
Proceeds from revolving credit facility	$ 12,000,000
Credit Agreement [Member] \| Term Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity	$ 415,000,000
Credit facilities, maturity	5 years
Proceeds from term portion of credit agreement	$ 415,000,000
Parent Company and Domestic Subsidiaries [Member]
Debt Instrument [Line Items]
Percentage of capital stock pledged as collateral		100.00%
Foreign Subsidiaries [Member]
Debt Instrument [Line Items]
Percentage of capital stock pledged as collateral		65.00%