Condensed Consolidated Statements of Cash Flows (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 142,744us-gaap_ProfitLoss	$ 118,538us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred sales commissions	12,399	8,957
Non-cash long-term incentive compensation expense	3,387us-gaap_ShareBasedCompensation	6,101us-gaap_ShareBasedCompensation
Depreciation and other amortization	14,294	16,206
Unrealized (gains) on investments	(7,541)	(2,499)
Other, net	578us-gaap_OtherNoncashIncomeExpense	(171)us-gaap_OtherNoncashIncomeExpense
Changes in assets and liabilities:
(Increase) decrease in segregated cash and securities	(43,862)	80,737
(Increase) in receivables	(125,720)us-gaap_IncreaseDecreaseInReceivables	(125,446)us-gaap_IncreaseDecreaseInReceivables
Decrease in investments	42,310	11,473
(Increase) in deferred sales commissions	(15,991)	(9,815)
(Increase) in other assets	(18,756)	(33,991)
Increase in payables	181,581	24,294
Increase in accounts payable and accrued expenses	988	2,652
Increase in accrued compensation and benefits	73,370	29,654
Net cash provided by operating activities	259,781	126,690
Cash flows from investing activities:
Purchases of investments	(85)	(190)
Proceeds from sales of investments	0	42
Purchases of furniture, equipment and leasehold improvements	(5,050)	(4,345)
Proceeds from sales of furniture, equipment and leasehold improvements	33	23
Net cash used in investing activities	(5,102)	(4,470)
Cash flows from financing activities:
Issuance of commercial paper, net	11,295	104,497
Increase (decrease) in overdrafts payable	38,772	(41,517)
Distributions to General Partner and Unitholders	(173,075)us-gaap_PaymentsOfDividendsCommonStock	(178,994)us-gaap_PaymentsOfDividendsCommonStock
Contributions from non-controlling interests in consolidated entities	202	0
Capital contributions from General Partner	335	437
Capital contributions from AB Holding	6,019	5,798
Payment for contingent payment arrangements	(213)us-gaap_RepaymentsOfOtherDebt	(517)us-gaap_RepaymentsOfOtherDebt
Additional investments by AB Holding with proceeds from exercise of compensatory options to buy AB Holding Units	3,901	4,656
Purchases of AB Holding Units to fund long-term incentive compensation plan awards, net	(16,929)	(3,385)
Purchases of AB Units	(11)	(229)
Other	(7)	(9)
Net cash used in financing activities	(129,711)	(109,263)
Effect of exchange rate changes on cash and cash equivalents	(9,183)	2,271
Net increase in cash and cash equivalents	115,785	15,228
Cash and cash equivalents as of beginning of the period	555,503	509,891
Cash and cash equivalents as of end of the period	$ 671,288	$ 525,119

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The amount of expense recognized in the current period for the periodic realization of capitalized fees that were paid to salespeople, distributors, brokers, and agents at the time of the conclusion of the sale. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.