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Share-Based Compensation Arrangement by Share-Based Payment Award, Remaining Number of Shares Available for Future Issuance

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Number of shares that have been repurchased and retired during the period.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events - Additional Information (Details) $ in Millions				6 Months Ended
	Jul. 10, 2025 shares	Dec. 19, 2024 shares	Apr. 01, 2024 USD ($) jointVentureHoldingCompany	Jun. 30, 2025 jointVenture shares	Jul. 24, 2025	Jul. 01, 2025	Dec. 31, 2024 jointVentureHoldingCompany shares
Subsequent Event [Line Items]
Retirement of AB Holding units (in shares)				1,082,242
Number of joint venture entities				2			2
Outside of North America
Subsequent Event [Line Items]
Number of joint venture entities \| jointVentureHoldingCompany							1
North America
Subsequent Event [Line Items]
Number of joint venture entities \| jointVentureHoldingCompany							1
Joint Venture Holding Companies
Subsequent Event [Line Items]
Number of joint venture entities \| jointVentureHoldingCompany			2
Cash proceeds \| $			$ 304.0
Consideration for future purchase option \| $			$ 102.6
Joint Venture Holding Companies \| Outside of North America
Subsequent Event [Line Items]
Number of joint venture entities \| jointVentureHoldingCompany			1
Interest in the joint venture				49.00%
Joint Venture Holding Companies \| North America
Subsequent Event [Line Items]
Number of joint venture entities \| jointVentureHoldingCompany			1
Interest in the joint venture			66.70%
Societe Generale \| Joint Venture Holding Companies
Subsequent Event [Line Items]
Interest in the joint venture			51.00%
Option to acquire controlling interest in joint venture, term			5 years
Societe Generale \| Joint Venture Holding Companies \| Outside of North America
Subsequent Event [Line Items]
Interest in the joint venture			51.00%
AB \| EQH and its subsidiaries
Subsequent Event [Line Items]
General partnership interest (as a percent)				1.00%
Subsequent Event \| Societe Generale \| Joint Venture Holding Companies
Subsequent Event [Line Items]
Interest in the joint venture						51.00%
Subsequent Event \| AB Corporation \| Joint Venture Holding Companies
Subsequent Event [Line Items]
Interest in the joint venture					66.70%
Subsequent Event \| AB Corporation \| Joint Venture Holding Companies \| Outside of North America
Subsequent Event [Line Items]
Interest in the joint venture					49.00%
Subsequent Event \| AB \| General and Limited Partnership Interests \| EQH and its subsidiaries
Subsequent Event [Line Items]
General partnership interest (as a percent)	68.60%
AB Holding Units \| Master Exchange Agreement \| EQH
Subsequent Event [Line Items]
Retirement of AB Holding units (in shares)		5,211,194
AB Holding Units \| Amended Exchange Agreement \| EQH \| Subsequent Event
Subsequent Event [Line Items]
Retirement of AB Holding units (in shares)	19,682,946
AB Units \| Master Exchange Agreement \| EQH
Subsequent Event [Line Items]
Conversion of AB units (in shares)		5,211,194
AB Units \| Amended Exchange Agreement \| EQH \| Subsequent Event
Subsequent Event [Line Items]
Conversion of AB units (in shares)	19,682,946
Master Exchange Agreement
Subsequent Event [Line Items]
Issuance of AB units (in shares)		10,000,000
Number of shares available for future exchange (in shares)				4,788,806			4,788,806
Master Exchange Agreement \| Subsequent Event
Subsequent Event [Line Items]
Number of shares available for future exchange (in shares)	19,682,946