ORGANIZATIONS (Details)	12 Months Ended
	Dec. 31, 2017 segment client_channel	Dec. 31, 2016
Organization Basis Of Presentation [Line Items]
Number of reportable segments | segment	4
Number of main client channels | client_channel	3
AXA Equitable
Organization Basis Of Presentation [Line Items]
Economic interest in AllianceBernstein	29.00%	29.00%
Parent
Organization Basis Of Presentation [Line Items]
Economic interest in AllianceBernstein	64.70%	63.70%