Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 592,977	$ 570,839	$ 527,422
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred sales commissions	49,145	41,508	41,279
Non-cash long-term incentive compensation expense	176,160	176,636	159,020
Depreciation and other amortization	56,426	62,515	60,009
Unrealized losses (gains) on investments	29,281	13,343	(42,080)
Losses on real estate asset write-offs	0	429	3,837
Other, net	(2,888)	(1,819)	(70)
Changes in assets and liabilities:
(Increase) decrease in segregated cash and securities	(88,997)	504,307	570,742
(Increase) decrease in receivables	(121,985)	(444,536)	140,254
Decrease (increase) in investments	58,053	3,563	(10,781)
(Increase) in deferred sales commissions	(29,925)	(89,224)	(16,423)
(Increase) decrease in other assets	(42,690)	(6,375)	755
Increase (decrease) in payables	65,309	(85,226)	(867,447)
(Decrease) in accounts payable and accrued expenses	(39,047)	(64,588)	(51,880)
(Decrease) in accrued compensation and benefits	(34,645)	(51,283)	(9,076)
Net cash provided by operating activities	667,174	630,089	505,561
Cash flows from investing activities:
Purchases of investments	(168)	(492)	(7,702)
Proceeds from sales of investments	4,240	140	10,884
Purchases of furniture, equipment and leasehold improvements	(30,217)	(25,433)	(21,615)
Proceeds from sales of furniture, equipment and leasehold improvements	2	176	12
Purchase of businesses, net of cash acquired	0	(60,610)	(38,636)
Net cash used in investing activities	(26,143)	(86,219)	(57,057)
Cash flows from financing activities:
Issuance (repayment) of commercial paper, net	93,867	219,818	(55,754)
Increase (decrease) in overdrafts payable	79,540	(38,967)	52,277
Distributions to General Partner and Unitholders	(597,872)	(572,348)	(461,282)
Distributions to non-controlling interests in consolidated entities	(12,165)	(12,199)	(10,865)
Capital contributions from affiliates	2,041	511	1,820
Payments of contingent payment arrangements/purchase of shares	(5,027)	(759)	(4,426)
Additional investments by AB Holding with proceeds from exercise of compensatory options to buy AB Holding Units	9,233	18,955	15,138
Additional investments by AB Holding from distributions paid to AB consolidated rabbi trust	0	0	14,076
Purchases of AB Holding Units to fund long-term incentive compensation plan awards, net	(213,484)	(90,143)	(111,619)
Purchases of AB Units	(805)	(1,553)	(1,805)
Other	(26)	(1,546)	62
Net cash used in financing activities	(644,698)	(478,231)	(562,378)
Effect of exchange rate changes on cash and cash equivalents	(10,353)	(20,027)	(3,417)
Net (decrease) increase in cash and cash equivalents	(14,020)	45,612	(117,291)
Cash and cash equivalents as of beginning of the period	555,503	509,891	627,182
Cash and cash equivalents as of end of the period	541,483	555,503	509,891
Cash paid:
Interest paid	3,984	3,148	3,692
Income taxes paid	25,999	42,028	13,423
Non-cash investing activities:
Fair value of assets acquired	0	87,821	81,929
Fair value of liabilities assumed	0	1,342	26,193
Fair value of redeemable non-controlling interest recorded	0	16,504	0
Non-cash financing activities:
Payables recorded under contingent payment arrangements	$ 0	$ 9,365	$ 17,100