Business Description and Organization - Summary of Ownership Structure (Details) - AB	12 Months Ended
	Dec. 31, 2025
Ownership structure of AB Holding
Ownership structure percentages, including limited partnership units	100.00%
EQH and its subsidiaries
Ownership structure of AB Holding
Ownership structure percentages, including limited partnership units	68.20%
AB Holding
Ownership structure of AB Holding
Ownership structure percentages, including limited partnership units	31.10%
Unaffiliated holders
Ownership structure of AB Holding
Ownership structure percentages, including limited partnership units	0.70%