Business Description, Organization and Basis of Presentation - Limited Partnership Interests in AB Holdings (Details) - AllianceBernstein Corporation	3 Months Ended
	Mar. 31, 2022
EQH and its subsidiaries
Distribution Made to Limited Partner [Line Items]
Limited partners or members ownership interest in Company (percent)	63.00%
AB Holding
Distribution Made to Limited Partner [Line Items]
Limited partners or members ownership interest in Company (percent)	36.30%
Unaffiliated holders
Distribution Made to Limited Partner [Line Items]
Limited partners or members ownership interest in Company (percent)	0.70%
AB
Distribution Made to Limited Partner [Line Items]
Limited partners or members ownership interest in Company (percent)	100.00%