Document and Entity Information Document	3 Months Ended
	Mar. 31, 2012	Oct. 27, 2011
Entity Information [Line Items]
Entity Registrant Name	ACACIA RESEARCH CORP
Entity Central Index Key	0000934549
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Amendment Flag	false
Amendment Description
Entity Common Stock, Shares Outstanding		49,701,283