Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Jul. 20, 2015
Document and Entity Information
Entity Registrant Name	ALLSTATE CORP
Entity Central Index Key	0000899051
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Common Stock, Shares Outstanding		400,389,900