Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	$ 980,938	$ 1,087,770	$ 3,122,551	$ 3,149,368
Not subject to contracts with customers:
Dividend and interest income, net of interest expense	9,668	7,834	31,960	23,298
Investment (losses) gains	(3,861)	(2,724)	(91,105)	3,385
Other revenues	239	(48)	709	869
Total revenue not from contract with customer	6,046	5,062	(58,436)	27,552
Net revenues	986,984	1,092,832	3,064,115	3,176,920
Base fees
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	700,809	758,524	2,145,307	2,169,932
Performance-based fees
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	13,755	18,273	112,515	87,955
Bernstein research services
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	91,557	113,340	315,806	338,016
All-in-management fees
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	69,717	89,737	224,337	260,992
12b-1 fees
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	16,594	21,681	53,547	62,368
Other distribution fees
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	61,649	59,194	191,547	150,390
Shareholder servicing fees
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	21,474	23,495	66,282	67,573
Other
Disaggregation of Revenue [Line Items]
Revenue subject to contracts with customers	$ 5,383	$ 3,526	$ 13,210	$ 12,142