Consolidated Company-Sponsored Investment Funds - Summary of Balance Sheet Amounts (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Condensed Balance Sheet Statements, Captions [Line Items]
Total assets	$ 9,784,121	$ 11,138,931
Liabilities	5,276,656	6,292,635
Redeemable non-controlling interest	182,934	368,656
Partners' capital attributable to AB Unitholders	4,324,531	4,477,640	$ 3,943,647
Total liabilities, redeemable non-controlling interest and capital	9,784,121	11,138,931
Company-sponsored investment funds
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	13,247	19,751
Investments	319,805	516,536
Other assets	14,434	44,424
Total assets	347,486	580,711
Liabilities	14,301	55,529
Redeemable non-controlling interest	182,934	368,656
Partners' capital attributable to AB Unitholders	150,251	156,526
Total liabilities, redeemable non-controlling interest and capital	347,486	580,711
VIEs
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	13,247	19,751
Investments	297,386	516,536
Other assets	13,516	44,424
Total assets	324,149	580,711
Liabilities	13,363	55,529
Redeemable non-controlling interest	176,307	368,656
Partners' capital attributable to AB Unitholders	134,479	156,526
Total liabilities, redeemable non-controlling interest and capital	324,149	580,711
VOEs
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	0	0
Investments	22,419	0
Other assets	918	0
Total assets	23,337	0
Liabilities	938	0
Redeemable non-controlling interest	6,627	0
Partners' capital attributable to AB Unitholders	15,772	0
Total liabilities, redeemable non-controlling interest and capital	$ 23,337	$ 0