Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities:
Net income	$ 890,733	$ 547,918
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred sales commissions	40,152	26,506
Non-cash long-term incentive compensation expense	27,442	19,109
Depreciation and other amortization	69,673	68,868
Non-cash lease expense	90,913	76,745
Remeasurement of contingent payment arrangements	(128,505)	13,115
Other, net	16,963	18,102
Changes in assets and liabilities:
Decrease in securities, segregated	320,911	594,497
(Increase) decrease in receivables	(61,177)	332,161
(Increase) in deferred sales commissions	(110,642)	(47,442)
(Decrease) in other liabilities of consolidated company-sponsored investment funds	(7,604)	(41,228)
(Decrease) in payables	(504,165)	(1,253,296)
Increase (decrease) in accounts payable and accrued expenses	79,860	(2,656)
Increase in accrued compensation and benefits	394,899	366,485
Cash payments to relieve operating lease liabilities	(62,165)	(80,678)
Net cash provided by operating activities	1,140,051	790,317
Cash flows from investing activities:
Purchases of furniture, equipment and leasehold improvements	(99,930)	(21,399)
Divestiture of business (includes $304.0 million in cash proceeds)	(40,196)	0
Capital contribution to equity method investments	(39,401)	0
Debt repayment from equity method investments	86,200	0
Net cash contribution (to) affiliates	(902)	(2,499)
Net cash (used in) investing activities	(94,229)	(23,898)
Cash flows from financing activities:
(Repayment of) debt, net	(654,316)	(90,000)
(Decrease) in overdrafts payable	(2)	0
Distributions to General Partner and Unitholders	(709,424)	(630,789)
Purchases of AB Holding Units to fund long-term incentive compensation plan awards, net	(73,131)	(70,837)
Other, net	(7,011)	(3,523)
Net cash (used in) financing activities	(1,543,349)	(991,497)
Effect of exchange rate changes on cash and cash equivalents	7,916	(2,240)
Net (decrease) in cash and cash equivalents	(489,611)	(227,318)
Cash and cash equivalents as of beginning of the period	1,160,889	1,309,017
Cash and cash equivalents as of end of the period	671,278	1,081,699
Excluding Company-Sponsored Investment Funds
Adjustments to reconcile net income to net cash provided by operating activities:
Unrealized (gains) on investments	(13,901)	3,892
Equity in earnings of equity method investments	35,443	0
(Gain) on divestiture	(134,555)	0
Changes in assets and liabilities:
Decrease (increase) in investments	18,880	(24,726)
Decrease (increase) in other assets	26,187	(53,776)
Company-Sponsored Investment Funds
Adjustments to reconcile net income to net cash provided by operating activities:
Unrealized (gains) on investments	(20,900)	(22,413)
Changes in assets and liabilities:
Decrease (increase) in investments	151,045	219,144
Decrease in other assets of consolidated company-sponsored investment funds	20,564	29,990
Cash flows from financing activities:
(Redemptions) of non-controlling interest in consolidated company-sponsored investment funds, net	$ (99,465)	$ (196,348)