Business Segment Information - Net Revenues Derived From Investment Management, Research and Related Services (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenues:
Total revenues	$ 4,559,652	$ 4,262,864	$ 4,120,728
Less: Broker-dealer related Interest expense	84,513	107,541	66,438
Net revenues	4,475,139	4,155,323	4,054,290
Reportable Segment
Revenues:
Total revenues	4,559,652	4,262,864	4,120,728
Less: Broker-dealer related Interest expense	84,513	107,541	66,438
Net revenues	4,475,139	4,155,323	4,054,290
Institutions | Reportable Segment
Revenues:
Total revenues	700,796	666,670	659,983
Retail | Reportable Segment
Revenues:
Total revenues	2,311,317	1,926,020	2,000,908
Private Wealth Management | Reportable Segment
Revenues:
Total revenues	1,245,891	1,052,843	1,004,003
Bernstein Research Services | Reportable Segment
Revenues:
Total revenues	96,222	386,142	416,273
Other | Reportable Segment
Revenues:
Total revenues	$ 205,426	$ 231,189	$ 39,561