Business Description, Organization and Basis of Presentation - Additional Information (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Total amount of AB Holding units purchased (in shares)	400,000	900,000	1,200,000	1,000,000.0
Tender Offer
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Cash tender offer to purchase up to (in shares)	46,000,000		46,000,000
Total amount of AB Holding units purchased (in shares)	19,682,946
AB Holding
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Economic interest, percentage	17.90%		17.90%
AB Holding | AB Corporation
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
General partnership interest in company (percent)			1.00%
AB Holding | AB Corporation | General Partnership Interest
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
General partnership number of general partnership units owned in holding company (in shares)	100,000		100,000
AB
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Economic interest, percentage	68.60%		68.60%
AB | AB Corporation | General Partnership Interest
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
General partnership interest in company (percent)			1.00%
AB | EQH and its subsidiaries
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
General partnership interest in company (percent)			1.00%