Condensed Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenues:
Dividend and interest income	$ 36,137	$ 43,986	$ 70,487	$ 88,501
Investment (losses)	(7,825)	(23,629)	(28,363)	(11,886)
Other revenues	33,912	39,167	64,092	64,460
Total revenues	1,104,569	1,049,756	2,202,693	2,177,624
Less: Broker-dealer related interest expense	15,662	21,813	33,179	45,530
Net revenues	1,088,907	1,027,943	2,169,514	2,132,094
Expenses:
Employee compensation and benefits	439,554	423,324	860,085	876,096
Promotion and servicing:
Amortization of deferred sales commissions	21,150	13,348	41,311	25,147
Trade execution, marketing, T&E and other	40,819	40,940	77,332	95,931
General and administrative	148,018	145,732	295,953	283,642
Contingent payment arrangements	42	2,558	106	5,116
Interest on borrowings	8,463	11,313	15,601	28,683
Amortization of intangible assets	11,246	11,531	22,483	23,303
Total expenses	866,813	828,654	1,711,051	1,690,808
Operating income	222,094	199,289	458,463	441,286
Gain on divestiture	0	134,555	0	134,555
Non-operating income	0	134,555	0	134,555
Pre-tax income	222,094	333,844	458,463	575,841
Income taxes	14,806	20,092	29,481	36,134
Net income	207,288	313,752	428,982	539,707
Net (loss) income of consolidated entities attributable to non-controlling interests	(3,179)	4,180	(2,284)	12,208
Net income attributable to AB Unitholders	$ 210,467	$ 309,572	$ 431,266	$ 527,499
Earnings Per Unit [Abstract]
Basic net income per AB Unit (in dollars per share)	$ 0.71	$ 1.07	$ 1.46	$ 1.82
Diluted net income per AB Unit (in dollars per share)	$ 0.71	$ 1.07	$ 1.46	$ 1.82
Investment advisory and services fees
Revenues:
Revenue subject to contracts with customers	$ 843,978	$ 817,327	$ 1,699,090	$ 1,601,732
Bernstein research services
Revenues:
Revenue subject to contracts with customers	0	0	0	96,222
Distribution revenues
Revenues:
Revenue subject to contracts with customers	198,367	172,905	397,387	338,595
Promotion and servicing:
Distribution-related payments	$ 197,521	$ 179,908	$ 398,180	$ 352,890