Document and Entity Information - USD ($)	12 Months Ended
	Mar. 31, 2018	May 21, 2018	Sep. 30, 2017
Document and Entity Information
Entity Registrant Name	ACXIOM CORP
Entity Central Index Key	0000733269
Document Type	10-K
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 1,887,964,114
Entity Common Stock, Shares Outstanding		77,060,281
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY