    <SEC-DOCUMENT>0000935036-21-000030-index.html : 20210506
    <SEC-HEADER>0000935036-21-000030.hdr.sgml : 20210506
    <ACCEPTANCE-DATETIME>20210506090130
    ACCESSION NUMBER:		0000935036-21-000030
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		31
    CONFORMED PERIOD OF REPORT:	20210506
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20210506
    DATE AS OF CHANGE:		20210506

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			ACI WORLDWIDE, INC.
    		CENTRAL INDEX KEY:			0000935036
    		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
    		IRS NUMBER:				470772104
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-25346
    		FILM NUMBER:		21896106

    	BUSINESS ADDRESS:
    		STREET 1:		3520 KRAFT ROAD, SUITE 300
    		CITY:			NAPLES
    		STATE:			FL
    		ZIP:			34105
    		BUSINESS PHONE:		239-403-4600

    	MAIL ADDRESS:
    		STREET 1:		3520 KRAFT ROAD, SUITE 300
    		CITY:			NAPLES
    		STATE:			FL
    		ZIP:			34105

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	TRANSACTION SYSTEMS ARCHITECTS INC
    		DATE OF NAME CHANGE:	19950109
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>8-K
    <SEQUENCE>1
    <FILENAME>aciw-20210506.htm
    <DESCRIPTION>8-K
    <TEXT>
    Document 1 - file: aciw-20210506.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.1
    <SEQUENCE>2
    <FILENAME>aciw-20210506ex_991.htm
    <DESCRIPTION>EX-99.1
    <TEXT>
    Document 2 - file: aciw-20210506ex_991.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.2
    <SEQUENCE>3
    <FILENAME>aciw-20210506ex_992.htm
    <DESCRIPTION>EX-99.2
    <TEXT>
    Document 3 - file: aciw-20210506ex_992.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.SCH
    <SEQUENCE>4
    <FILENAME>aciw-20210506.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT
    <TEXT>
    Document 4 - file: aciw-20210506.xsd

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.CAL
    <SEQUENCE>5
    <FILENAME>aciw-20210506_cal.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION CALCULATION LINKBASE DOCUMENT
    <TEXT>
    Document 5 - file: aciw-20210506_cal.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.DEF
    <SEQUENCE>6
    <FILENAME>aciw-20210506_def.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION DEFINITION LINKBASE DOCUMENT
    <TEXT>
    Document 6 - file: aciw-20210506_def.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.LAB
    <SEQUENCE>7
    <FILENAME>aciw-20210506_lab.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION LABEL LINKBASE DOCUMENT
    <TEXT>
    Document 7 - file: aciw-20210506_lab.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.PRE
    <SEQUENCE>8
    <FILENAME>aciw-20210506_pre.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT
    <TEXT>
    Document 8 - file: aciw-20210506_pre.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>9
    <FILENAME>aciw-20210506ex_992001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: aciw-20210506ex_992001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>aciw-20210506ex_992002.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: aciw-20210506ex_992002.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>11
    <FILENAME>aciw-20210506ex_992003.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 11 - file: aciw-20210506ex_992003.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>aciw-20210506ex_992004.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 12 - file: aciw-20210506ex_992004.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>13
    <FILENAME>aciw-20210506ex_992005.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 13 - file: aciw-20210506ex_992005.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>14
    <FILENAME>aciw-20210506ex_992006.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 14 - file: aciw-20210506ex_992006.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>15
    <FILENAME>aciw-20210506ex_992007.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 15 - file: aciw-20210506ex_992007.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>16
    <FILENAME>aciw-20210506ex_992008.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 16 - file: aciw-20210506ex_992008.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>17
    <FILENAME>aciw-20210506ex_992009.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 17 - file: aciw-20210506ex_992009.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>18
    <FILENAME>aciw-20210506ex_992010.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 18 - file: aciw-20210506ex_992010.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>19
    <FILENAME>aciw-20210506ex_992011.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 19 - file: aciw-20210506ex_992011.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>20
    <FILENAME>aciw-20210506ex_992012.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 20 - file: aciw-20210506ex_992012.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>21
    <FILENAME>aciw-20210506ex_992013.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 21 - file: aciw-20210506ex_992013.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>22
    <FILENAME>aciw-20210506ex_992014.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 22 - file: aciw-20210506ex_992014.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>23
    <FILENAME>aciw-logo1.jpg
    <TEXT>
    Document 23 - file: aciw-logo1.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>24
    <FILENAME>aciw-20210506_htm.xml
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 24 - file: aciw-20210506_htm.html

    Document 24 - RAW XML: aciw-20210506_htm.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>25
    <FILENAME>R1.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 25 - file: R1.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EXCEL
    <SEQUENCE>26
    <FILENAME>Financial_Report.xlsx
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 26 - file: Financial_Report.xlsx

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>27
    <FILENAME>Show.js
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 27 - file: Show.js

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>28
    <FILENAME>report.css
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 28 - file: report.css

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>29
    <FILENAME>FilingSummary.xml
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 29 - file: FilingSummary.html

    Document 29 - RAW XML: FilingSummary.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>JSON
    <SEQUENCE>31
    <FILENAME>MetaLinks.json
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 31 - file: MetaLinks.json

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>ZIP
    <SEQUENCE>32
    <FILENAME>0000935036-21-000030-xbrl.zip
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 32 - file: 0000935036-21-000030-xbrl.zip

    </DOCUMENT>
    </SEC-DOCUMENT>